I have looked under the phone and hit the top 3 dots and clicked settings but I do not see any option to forward calls.
Dialer -> top right 3 dots -> Settings -> Calls -> Call forwarding
Network & Internet - Internet - Gear Icon on the top right - Access Point Names. When I try to add or remove APN settings it does nothing unless I delete the Verizon APN settings. Then it allows me to add a new one. The only thing I can do is edit the top 2 APNS but there are two additional ones below that do not have the option of editing or deleting. If I reset to default it brings back the VPN settings. I am using a Verizon MVNO and there are 4 APN settings. Verizon can be deleted or edited, T-mobile US - cannot be deleted or edited, Verizon - can be deleted or edited, T-mobile MMS -settings cannot be changed or deleted
You cannot edit the APNs which are preloaded into the OS, you need to add new ones.
Post your carrier version string in Settings -> Network and Internet -> SIMs
Also see: https://grapheneos.org/usage#carrier-functionality