This can be answered by a bunch of RFCs and W3c specs. These are the frameworks those other frameworks are built on top. So here re some recommendations
I am not saying read that and learn all contents like in school. Just try the things in there and read up on the theory to the practice. As pointed out other places: You will encounter problems, know what they are and use frameworks to solve them. But just try practically do it yourself for a moment
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