Here is a project where they used pallets:
You could also do fencing around the outside much as they did the pallets. Building a deck around them is very popular in this area then covering the side areas with lattice.
Build a deck around it, at least one one “side”.
If you are going to use wood, use exterior treated lumber so it lasts more than a season or two. Pallet wood will rot quickly.
Depending upon your DIY skills there are some inspirational ideas here https://jekyllandhydemusical.com/above-ground-pool-ideas/ (many beyond me!)