My question is 2 parts:

1: Deck: I have an older deck that has a lot of paint coming up. I have 2 big labs that run across it so the wood is splintered in the higher traffic areas with some deeper grooves. I was wondering if there is anything I can do to it short of replacing the whole deck. The grooves may be too deep to sand and repaint, but I didn't know if there was any type of paint/filler that would help fill in the grooves

2: Fence: I recently pressure washed my wooden fence around my pool (small fence) and it brought it back to life from the green and black color. The wood here is old as well, so I was wondering what the best way to treat this, either with stain or paint, to help preserve it longer as well.

Trying to eek out some more time on these 2 items, any help would be appreciated.

The fence can be stained with something like Thompsons Water Seal Plus Wood Protector . Thompson's Wood Protector, 1 Gal # 11831 by Thompson's Water Seal It comes clear or 5 tints. The deck is a goner from my view. Paint on a deck already, mo good exterior fillers for deck wood. I'd replace with 5/4 pressure treaed pine for a cost advantage.