Can I set up transaction fees to add a % to liquidity pool?

So I am currently working on a project with a small team. We were handed an asset that was already created. My question is, is there anyway we can edit the contract to charge a small fee everytime there is a transaction and add that fee amount to the liquidity pool? We are all new at this and we just want to learn if it’s possible and if so, how would we achieve it?

If it helps, the asset was created using Algodesk.

Check out arc-18: