Both on-chain and lightning wallets can receive any amount.  An invoice is just a convenient URL  or QR code to say "please send this amount to this address".

I've never used Mutiny but there should be a way to find what your address is.  Alby and Primal are just different services to host a lightning wallet just like Mutiny.  You only need one and whichever service you prefer is fine.  Maybe #plebchain can provide a more detailed answer.