Ok but you can only exchange btc - just took a look - and what can you do with the USD? Not sure exactly how it would work unless I test it out myself.
The USD is received directly by you via whatever payment method you choose. If you choose a bank transfer, then you will get it directly in your bank account. If you choose some payment processor like Zelle or CashApp, then you'll receive the USD in your account on those apps. There is no wallet on these DEXs which stores USD for you.
Some of the ones I have listed above support a few select altcoins such as Monero. If you want to trade bitcoin/altcoin pairs, then there are a variety of non-KYC instant exchangers you can use, but I'm not familiar with this area so I can't recommend any. Maybe try the altcoin boards.