Mark Manson Tribute Page

Hello there! I’m a young CC student starting the FCC curriculum. (in short, I’m a newbie)
If you have the time, can you check my website?
You can see it here:
This is actually the first website I have coded, and I’m really excited about this even though I still gotta ways to go.

Also, I got some questions, if you can answer any of them I will be really thankful.

  1. Should I have used the figure tag in any part of my code?
  2. In some images I used the id name “material-thumbnail” and I don’t think is a proper naming, I’m a Spanish speaker and I’m still learning English to the fullest, what name would you have used?
  3. I read somewhere that most sites always should use the main tag, is that true? Did I use it correctly here?
  4. Any tips or guides I should check out to have a better CSS structure?