This is a readily solvable problem i.e. the only phone number I use/give online is a VOIP# that just redirects to voicemail immediately (and blocks the call if it's on my SPAMMER list of persistent annoyances).
For friends/family they have my cell# and it only lets calls through if they're in my contacts.
For friends/family they have my cell# and it only lets calls through if they're in my contacts.