What to learn for Angular?

Question

Angular

Hello everyone)
Tell me what to teach, read on Angular, or rather, probably to say its features?
They advised to pay attention to: RxJs , Mobix , Socket ... Can you tell me some more frequently encountered, useful, etc. features, if possible, a link to a lesson, documentation, an article that you think might be useful.
Thank you!

Answer 1

https://angular.io/tutorial
https://coursehunters.net/course/angular-4-c-nulya...
https://coursehunters.net/course/itvdn-typescript-...
https:// www.learnrxjs.io/
And further if necessary:
​​For example, ngrx, ngx-boootstrap, angular universal, angular material