Use a decent VPS instead of trying to host off a residential internet connection behind 47 layers of NAT and you don’t have to worry about 90% of that stuff

i.e. use the right tool for the job

if they use TCP, you can, sort of, but any client that wants to connect will need to use Cloudflared

https://developers.cloudflare.com/cloudflare-one/applications/non-http/arbitrary-tcp/

you can skip the Cloudflare Access, probably (I’ve never tried any of this myself)