Bonsoir!
I’ll offer what help I can, although I’m no expert as I’ve only been working here in France for the last six years.
Firstly, well done with your decision to learn French, many people think they can get by without but the harsh reality is that if you’re working here you’ll need a half-decent level in the local language.
As for the required qualifications, you’ll have no issues with a UK license and DCPC as both are valid Europe-wide.
To get a better idea of what work is available in an area that interests you have a look at the free ads:
Just enter your geographical criteria and enter ‘chauffeur pl’ or ‘chauffeur spl’ in the search box and you’ll come up with a bunch of jobs, many of them either short term contracts (CDD) or agency ‘interim’ work. That’ll tell you a lot about what’s available up there in Normandie. Don’t forget that while houses are generally less costly than in the UK the rate of pay is most often lower. 1500/1800 euros net is a representative ballpark sum for a week’s work, without nights out.
Hope that helps a bit. Bon courage!
Craig