Personally I would say the div tag (without argument) can be used as a section,but as you learn I suggest you practice the way it's taught and use the section when you have a certain section in your web page, you might ask "what do I mean by this?" well for example you could have a section dedicated to your videos,but now you want to group them together,That's where the div tag comes into play,so you use the div tag to group certain elements on your page
<h1>My recent videos</h1> <!— This is the section's title →
Your videos would go here as you want them to be in one place
I hope this information helps you.