Just purchased a PPP, how screwed am I?

[GhostLegion]

The title sounds negative but I say it with humor. Just to set my expectations, I'm currently using an F1 Orchid by Sunbeam Wireless. It's a flip phone and my phone before that was a iPhone 12 Mini. So I've already gone through the stage of losing essentially all smartphone functionality and on top of that, because the flip phone I use is from a niche manufacturer, I've even experienced the joys of carrier whitelists. So really, the only expectation I have is that the PPP function as a phone. I need it to be able to consistently receive calls and SMS/MMS whether suspended or not. Any particular US carrier recommended for best compatibility? Which OS/DE is most recommended currently for my purposes? I've looked at past threads but none seem current or answer the questions I have. My plan was to use pmOS with KDE as my ideal scenario but I could get used to GNOME or Phosh if needed. I plan on flashing the FOSS firmware for the modem as reports seem to indicate it improves the experience.

How is the software development progressing and where can I contribute monetarily? I looked at pmOS but they aren't interested in such donations.