The first piece you need to master is to pick HTML up very well. There are many online free but high quality video tutorials, you can follow. Let me list out a few of them. Most of them do not assume any prior knowledge or understanding. So, they all should be good to go.
Flexbox Tutorial – https://www.youtube.com/watch?v=k32voqQhODc&t=470s
A theme design by css and flexbox
A video showing how to call an API using Python