Why not just use bitcoin or lightning channels?
And if you want this service to really succeed, you need a place to just paste a credit card and have it do a preauth...
An easy wallet to try is Coinomi. It's an app that installs on your phone and has a built-in exchange. Here are some links to install it:
Coinomi on iOS https://apps.apple.com/us/app/coinomi-wallet/id1333588809
Coinomi on Android https://play.google.com/store/apps/details?id=com.coinomi.wa...
If you're looking for a Litecoin wallet for the desktop, try Electrum-LTC https://electrum-ltc.org/. After you create a wallet, you can exchange some Bitcoins for Litecoins through https://swapspace.co/
I don't know much about lightning network channels. I'll look into it. Thanks!
On using a credit card, I built something similar that could take a credit card through Stripe. The problem there is people are a bit reluctant to type in their credit card number, in case the number gets stolen. Crypto is safer for this because the private key stays with the user on their phone or desktop wallet. Also, pasting the credit card, expiration, and your name takes longer than scanning a QR code with your phone.