Not meaning to be a smartass, but a ferry to NL and either train or ferry to France. Or a plane.
If you do a search here you'll find more information about travelling with a bike.
The problem is that Covid has completely messed everything up.
I believe at least one ferry from the UK no longer takes bikes.
I rode from NL to Ireland and back again (4 ferries) and booked a spot twice the night before by phone (NL/Hull) once at the terminal for the next day (Wales) and one the same day (Belfast). Not sure I'd take that approach now!
Depending on your cycling style, given the uncertainty, it might be worthwhile looking at companies who do organised/supported self navigating tours. A bit more expensive, but a lot less stress and it's their job to deal with any Covid fallout.
Good luck!