What product(s) do you want to build? Your submission suggests it might be one or more things. "API for Building a Bank?" Do you want to take customer deposit

What product(s) do you want to build? Your submission suggests it might be one or more things. "API for Building a Bank?" Do you want to take customer deposits? "Stripe" Do you want to sell stuff to people, and allow them to pay you by card? "SynapseFi" Do you want to engage the services of another company, which is a bank, so that you can, e.g. issue payment cards? Based on the lack of specificity in your post, maybe one or more of the following applies? A) You aren't sure what you want to build yet? B) You want to provide a wide range of retail banking products? C) You're still getting up to speed with what banks, card networks, processors etc. each do? Feel free to email me (address in profile) if you don't want to share here. I've only recently moved to the US, but have launched financial products (covering payments, deposits and loans) in the UK, which is somewhat similar.