I see you posted the exact same question in http://forum.notebookreview.com/threads/should-i-create-an-apple-computer-account-before-or-after-initializing-configuring-my-laptop.816084/
Anyway, if you feel you need such an account (why?) open it with your new laptop. So, that is after initializing it (whatever you mean with initializing).
Although we certainly are willing to answer your other 17 questions, may I suggest you visit either a bookshop or a public library and find a nice book about using Apple machines? https://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=mac+os+high+sierra lists a few.
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