How to embed web page in SharePoint

You can insert an external web page using SharePoint Embed web part using iframe.

Let's take a look at this using step-by-step points using screenshots:

1. Open the SharePoint Page on which you want to embed a web page.
2. Now click on the Edit button (you will be able to see the edit button if you only have read access)
3. Now hover between web parts and click on the + sign.
   
4. Select the option Embed.
   
5. On the right size in the "Website address or embed code" add the iframe of the page that you want to add.
   
   Example:

   <iframe src="https://code2care.org/sharepoint/show-videos-on-sharepoint-page" width=300 height=300>

6. You should be able to see the preview of the page on the left side.
7. Once done, make sure to hit the Republish button to apply changes for all users.