You can quit at any second and just walk away with whatever chips you have in front of you that are not in the betting circle. However, you would actually quit at the completion of whatever hand you are playing as it would be stupid to walk away from a wager that you have placed while it still has a chance to win. Just like you wouldn't put money in a slot machine, hit the button and run away before the ching ching ching winning sound.
It would probably be more polite to walk away from the table at the completion of one game when the dealer scoops up the cards.
Thanks to Once Dear, Romes, and a large number of fellow posters, I was able to collect these suggestions BEFORE I played at my first BJ table! (By posting threads on the BJ Forum).
If your buy-in session is $100, QUIT after winning $40, losing $60, or when:
2.) You're counting and the TC stays < - 1
3.) When the players/dealers stink literally or figuratively.
4.) You are tired and start making sloppy mistakes.
5.) You need a bathroom break (the dealer can save your seat for a 10 min only). The dealer places a disc called a "lammer" on your betting circle.
6.) You're hungry/bored/distracted.
7.) The game is no longer fun (smoke, annoying seat mates, icy dealer, etc.).
8.) Tell the dealer you're on a break and stay in your seat for a while (unless you want to physically leave the area).
10.) Tell the dealer you need to take/make a call.
BTW, you can politely leave whenever you feel like it. If you don't put any money in the betting circle, they'll figure out you're done. An alert dealer will still double check and ask you, "Bets, please" or words to that effect.
A 2nd BTW is I agree with BleedingChipsSlowly that your 2 questions would probably be more suited to the BJ Forum vs starting a blog.
Technically, I'm a "newbie" too -- but I have 10 actual sit-down hours of experience from my first time venture this past Oct 2016. So if you're truly a rank beginner or newbie, here's an example of when you might use a blog:
Hope to hear from you in my blog!
Welcome to the forum. A good place to start learning Blackjack terminology is the introduction to the game given on the sister site Wizard of Odds. Try Getting Started: Blackjack for Beginners. By the way, your questions are a better fit on the forum style in the threads section rather than the blog. In this case I think a post to either the GAMBLING Blackjack or QUESTIONS AND ANSWERS Gambling threads would have gotten a better response. Good luck!