From where should I learn advanced HTML?.....Because in Sololearn there are only basics...and many tags and rules are missing..

Answer 1

w3schools.com or www.tutorialspoint.com will help

Answer 2

MDN ( Mozilla Developer Network ) is a great ressource to dive into avanced reference, still quit readable and multi-languages.
Mainly reference oriented ( more than tutorial like w3schools or tutorialspoint, even they povides some ), but very interesting stuff to study, learn and find a lot of functional examples...

https://developer.mozilla.org/

Answer 3

W3schools is a great reference