powerwash it very well let totaly dry and then you could roller it with like a Thompson’s water seal or paint what every you like
Hello Vicki! Here is some good information to consider: https://www.dummies.com/home-garden/exteriors/tips-for-painting-your-deck/
Use a UV deck stain. Paint will crack and peel. More work and a pain to strip and remove.
This is what I did: