I want to learn =) What do I do?)

Yes, you can if you are prepared to work hard) https://www.youtube.com/watch?v=d0yGdNEWdn0

"I remember every wand I sold, Mr. Potter." is incorrect because 'ever' is implied here and to a native speaker it would sound strange. "I remember every wand I ever sold, Mr. Potter." is incorrect also. When you have 'ever' - it's generally a clue to use a Present Perfect tense. Sometimes you don't have these markers (other common ones are 'never, ever, just, already, yet), so you should think of it as something that happened in the past but is important at the time of speaking).

both mean the same and are being used) However, "I do not work Monday mornings" is grammatically incorrect, since you need a preposition after the verb 'work" to clarify when. If you write an academic passage or an essay on a TOEFL, it would most certainly count as a mistake. But in a spoken English it is used quite often) As a sign of an negative attitude I think)

Юрист-человек с юридическим образованием) Адвокат более узкая направленность, это человек, который работает с людьми, представляет их интересы в суде, например) Пожарник или пожарный - одна и та же профессия) fireman)

Definitely not options 2 and 4 - you need to have a verb after which, as 'which' stands for the nearest noun (Oxford here). And you cannot have a noun without a verb. As for the usage of comma in options 1 and 3 - Use WHICH (and commas) if the modifier is non-essential. For this sentence it's not essential information that the person living in Oxford also lives in the city famous for its university. Hence, #1 option is the best one here)

I might be wrong, but I think if you have both options in one sentence "___ or ___" they have to agree in time used (present perfect here). So, maybe a grammatically better way to say this would be "Have you just woken up or have you stayed up late?". Both would be consistent in time used.