BTC for investment or long-term store of value. BCH, or various other alternatives (Litecoin, XRP, Stellar, cough Nano cough), for making payments. But if you can use the Lightning network, then BTC works for payments as well (arguably - in this space anything and everything is highly arguable).
If you're seriously looking down the track at using cryptocurrency, spend some time playing with small amounts of it to see how it all works. Different coins have different use-cases, and it's very confusing to come from zero knowledge. Also transferring and converting between different coin types can kill you in fees, so keep an eye on that as well.
And in doing your research don't believe what anyone says about anything, especially youtube folks. Find the most likely narratives amongst the jungle of snakes and traps, based on your own experience at detecting bullshit and applying logic.