You'll need a 2M transceiver with SSB mode to be able to do FT8. The FT-70D has FM and System Fusion but no SSB. However, you should be able to use Winlink via VARA FM (assuming a Winlink gateway in range) or APRS / packet with an appropriate interface and software. Several interface options are out there... this one looks interesting - Digirig Mobile 1.6