How long after I make a purchase with my bank card (used as credit card) can the charge show up on my account?

Is there a max time allowed by banks for the charge to be actually submitted? Does anyone have a good explination of how that all works with using bank cards as credit cards?

airline credits from your credit card?

would someone please explain to me how the airline credits are calculated on your credit card, tell me which trips you took and with which airlines (like which airlines accept those credits), and which credit card (which bank card) do you use.

What is the best credit card I can get to start building my credit with? Or how can I start building my credit?

Can I start building my credit by paying for things with my bank card and telling them to charge it on credit? (I do not know much about how to build my credit so please help me!)
Question: Best credit card to get to starting building credit and can I build my credit by using my [...]

how long does a refund take to a bank credit card ?

i bought a monitor at best buy had it for a day or two and didn’t like so i returned it how long will it take for the money too be refunded to my bank card (i used the credit mode to pay)
as i would like to by a new one online at newegg [...]