When I see it, I like the design of https://framework7.io
Left side: some basic HTML
Right side: HTML in phone
I like the design of the phone on the right side, how to I implement one and integrate it into my frontend, thanks.
Can you be more specific with your question here?
If you mean ‘how can I replicate the look of a mobile phone in HTML’, you’ll notice that the ‘phone’ on the Framework7 homepage is just a black rectangle with rounded corners. So you could easily create a div and use CSS to set a black border with rounded corners.
If you mean ‘how can I embed a website within another website’ try researching the iframe tag, starting at https://www.w3schools.com/tags/tag_iframe.ASP