I believe those do not provide a lightning address for you which you need to receive zaps on Nostr. If you want an easy experience then you can receive using a Alby lightning address. You need to create an account on the getalby website first. You would use it on a computer when you want to sweep the funds to a self-custodial wallet at some point.

Or if you want to be more adventurous you could start using nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg 's ecash method to receive zaps.