html element overflow problem

I am a newbie who is new to the basics of html, let me feel the love of the blogging community!

The following problem is an element overflow problem that I encountered based on my current understanding of HTML. I hope to get some advice from an experienced person.

The questions are as follows:

Hopefully there are many different solutions to this problem, and web page layout suggestions (hopefully there are some useful information).

Question 2: As a newbie, many enterprise-level front-end issues fill my brain, all filled with question marks. Experience is accumulated and precipitated at work. When I step into the front-end ranks, I hope that some experts can recommend some that are commonly used in enterprises today. Frameworks and learning methods.