Your story is quite fascinating! It's interesting how people with disdain to bitcoin can change their mind eventually. Some people seem to really, really hate it. I don't blame them - most of crypto world is terrible, and also speculating on Bitcoin is what is mainly seen outside, which is far from the true value it gives.
I am just surprised that you begin with BTCPay Server. This is used mostly by merchants, as it's payment processor and I think you need to run a full node for it, which is usually not something people start with :D You can try some lightning self-custodial wallets like Phoenix or Breez - those are actually lightning nodes in your phone!