To remove old paint I would heat gun the old paint off and give a light sand afterwards. I would also look to re caulk it. As to filling holes you can use most decent fillers. Doesn't have to be wood filler either.
im re doing some paving from a previous owner and they laid it just on sand.
im taking it up and am re doing on sub base and full bed.
can i re use the sand or is it massive no ? The paving is foottraffic only if that makes a difference?
Cheers
Dan