Click the button on web page a to make web page b fill the entire web page_html/css_WEB-ITnose

Click a button on a web page to display another web page in this web page. If the b web page is too large and needs a scroll bar, what should you do?
If you use a div to float the entire layer, what should you do specifically?

Reply to discussion (solution)

Use iframe to introduce the page you want to load. Set overflow: auto/scroll to scroll to view the excess content
According to your own needs Add CSS