1. will i be able to download coins from 2 separate wallets with ledger nano x, and keep them there or it's 1 wallet 1 ledger?
Not sure I get what you mean. Are you saying you have 2 wallets of X coins with different seeds and want to import both of them to Ledger? If that's so, I don't think you can do it.
2.are there any sites where i send xlm, and they send fiat currency to a credit card? i remember there was 1 site that did that few months ago, it didn't support my country, but i assume if there was 1,there are more? for instance id like to send 1k dollars to someone in africa, i send to that website 1k worth of stellar, and they send fiat to designated credit card of my recipient?
Have you tried Wirex? Probably not exactly what you're looking for but it could offer some options.
https://wirexapp.com/money-management3. is trust wallet good choice for keeping erc20 and bep2 tokens? their GUI is somewhat clanky for me, i dont like it too much, thats why im asking if there is a wallet with same functionality but with smoother GUI.
There's a list of recommended BEP2 wallet from CZ himself:
https://twitter.com/cz_binance/status/1119114145129844737?lang=enEnjin is probably one of the alternatives.
4.Im currently using CEX to buy and sell my crypto with fiat currency via credit cards, any cheaper or better alternatives?
Use Bisq.