Driving manual is not difficult, but unlike the opposite scenario, it’s not something you can learn with only short instructions.

It does take time to develop the motor skills in order do it without thinking about it. The practice wlll take maybe an afternoon or two if you do nothing else. I’d advise you to do it over more than one day to allow yourself to sleep on it and come back at it

Once you’ve learned it, you’ll never think about it again though.