diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..30bc162
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/node_modules
\ No newline at end of file
diff --git a/README.md b/README.md
index e464a55..04caee1 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ Generate a simple PDF invoice from HTML using [puppeteer](https://github.com/Goo
 ## How to use
 
 - Run `npm install` to install package in package.json
-- Run `node pdf.js` to generate invoice.pdf
+- Run `node example.js` to generate invoice.pdf
 
 ## The PDF Invoice from HTML
 
@@ -24,51 +24,15 @@ Generate a simple PDF invoice from HTML using [puppeteer](https://github.com/Goo
 2. Using handlebars to binding data to content html
 3. Using Puppeteer to generate pdf from final html
 
+index.js
+
 ```js
-const fs = require("fs");
-const path = require("path");
 const puppeteer = require("puppeteer");
 const handlebars = require("handlebars");
 
-(async () => {
-  var dataBinding = {
-    items: [
-      {
-        name: "item 1",
-        price: 100,
-      },
-      {
-        name: "item 2",
-        price: 200,
-      },
-      {
-        name: "item 3",
-        price: 300,
-      },
-    ],
-    total: 600,
-    isWatermark: false,
-  };
-
-  var templateHtml = fs.readFileSync(
-    path.join(process.cwd(), "invoice.html"),
-    "utf8"
-  );
-  var template = handlebars.compile(templateHtml);
-  var finalHtml = encodeURIComponent(template(dataBinding));
-
-  var options = {
-    format: "A4",
-    headerTemplate: "<p></p>",
-    footerTemplate: "<p></p>",
-    displayHeaderFooter: false,
-    margin: {
-      top: "40px",
-      bottom: "100px",
-    },
-    printBackground: true,
-    path: "invoice.pdf",
-  };
+module.exports.html_to_pdf = async ({ templateHtml, dataBinding, options }) => {
+  const template = handlebars.compile(templateHtml);
+  const finalHtml = encodeURIComponent(template(dataBinding));
 
   const browser = await puppeteer.launch({
     args: ["--no-sandbox"],
@@ -80,7 +44,62 @@ const handlebars = require("handlebars");
   });
   await page.pdf(options);
   await browser.close();
-})();
+};
+```
+
+example.js
+
+```js
+const fs = require("fs");
+const path = require("path");
+const { html_to_pdf } = require(".");
+
+try {
+  (async () => {
+    const dataBinding = {
+      items: [
+        {
+          name: "item 1",
+          price: 100,
+        },
+        {
+          name: "item 2",
+          price: 200,
+        },
+        {
+          name: "item 3",
+          price: 300,
+        },
+      ],
+      total: 600,
+      isWatermark: true,
+    };
+
+    const templateHtml = fs.readFileSync(
+      path.join(process.cwd(), "invoice.html"),
+      "utf8"
+    );
+
+    const options = {
+      format: "A4",
+      headerTemplate: "<p></p>",
+      footerTemplate: "<p></p>",
+      displayHeaderFooter: false,
+      margin: {
+        top: "40px",
+        bottom: "100px",
+      },
+      printBackground: true,
+      path: "invoice.pdf",
+    };
+
+    await html_to_pdf({ templateHtml, dataBinding, options });
+
+    console.log("Done: invoice.pdf is created!");
+  })();
+} catch (err) {
+  console.log("ERROR:", err);
+}
 ```
 
 ## How to display paid stamp watermark on invoice?
diff --git a/example.js b/example.js
new file mode 100644
index 0000000..cdfc7b2
--- /dev/null
+++ b/example.js
@@ -0,0 +1,50 @@
+const fs = require("fs");
+const path = require("path");
+const { html_to_pdf } = require(".");
+
+try {
+  (async () => {
+    const dataBinding = {
+      items: [
+        {
+          name: "item 1",
+          price: 100,
+        },
+        {
+          name: "item 2",
+          price: 200,
+        },
+        {
+          name: "item 3",
+          price: 300,
+        },
+      ],
+      total: 600,
+      isWatermark: true,
+    };
+
+    const templateHtml = fs.readFileSync(
+      path.join(process.cwd(), "invoice.html"),
+      "utf8"
+    );
+
+    const options = {
+      format: "A4",
+      headerTemplate: "<p></p>",
+      footerTemplate: "<p></p>",
+      displayHeaderFooter: false,
+      margin: {
+        top: "40px",
+        bottom: "100px",
+      },
+      printBackground: true,
+      path: "invoice.pdf",
+    };
+
+    await html_to_pdf({ templateHtml, dataBinding, options });
+
+    console.log("Done: invoice.pdf is created!");
+  })();
+} catch (err) {
+  console.log("ERROR:", err);
+}
diff --git a/index.js b/index.js
new file mode 100644
index 0000000..5ba78b1
--- /dev/null
+++ b/index.js
@@ -0,0 +1,18 @@
+const puppeteer = require("puppeteer");
+const handlebars = require("handlebars");
+
+module.exports.html_to_pdf = async ({ templateHtml, dataBinding, options }) => {
+  const template = handlebars.compile(templateHtml);
+  const finalHtml = encodeURIComponent(template(dataBinding));
+
+  const browser = await puppeteer.launch({
+    args: ["--no-sandbox"],
+    headless: true,
+  });
+  const page = await browser.newPage();
+  await page.goto(`data:text/html;charset=UTF-8,${finalHtml}`, {
+    waitUntil: "networkidle0",
+  });
+  await page.pdf(options);
+  await browser.close();
+};
diff --git a/invoice.pdf b/invoice.pdf
index 822a2c9..f1dc1b7 100644
Binary files a/invoice.pdf and b/invoice.pdf differ
diff --git a/package.json b/package.json
index afd6a8d..d86fe28 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
   "author": "chuongtrh",
   "license": "MIT",
   "dependencies": {
-    "handlebars": "^4.0.12",
-    "puppeteer": "^1.8.0"
+    "handlebars": "^4.7.7",
+    "puppeteer": "^14.2.0"
   }
 }
diff --git a/pdf.js b/pdf.js
deleted file mode 100644
index b6f7b9b..0000000
--- a/pdf.js
+++ /dev/null
@@ -1,57 +0,0 @@
-const fs = require("fs");
-const path = require("path");
-const puppeteer = require('puppeteer');
-const handlebars = require("handlebars");
-
-try {
-    (async () => {
-        var dataBinding = {
-            items: [{
-                name: "item 1",
-                price: 100
-            },
-            {
-                name: "item 2",
-                price: 200
-            },
-            {
-                name: "item 3",
-                price: 300
-            }
-            ],
-            total: 600,
-            isWatermark: true
-        }
-
-        var templateHtml = fs.readFileSync(path.join(process.cwd(), 'invoice.html'), 'utf8');
-        var template = handlebars.compile(templateHtml);
-        var finalHtml = encodeURIComponent(template(dataBinding));
-        var options = {
-            format: 'A4',
-            headerTemplate: "<p></p>",
-            footerTemplate: "<p></p>",
-            displayHeaderFooter: false,
-            margin: {
-                top: "40px",
-                bottom: "100px"
-            },
-            printBackground: true,
-            path: 'invoice.pdf'
-        }
-
-        const browser = await puppeteer.launch({
-            args: ['--no-sandbox'],
-            headless: true
-        });
-        const page = await browser.newPage();
-        await page.goto(`data:text/html;charset=UTF-8,${finalHtml}`, {
-            waitUntil: 'networkidle0'
-        });
-        await page.pdf(options);
-        await browser.close();
-
-        console.log('Done: invoice.pdf is created!')
-    })();
-} catch (err) {
-    console.log('ERROR:', err);
-}