Wood for pressure treatment is placed in a hermetically sealed vat, then all the air is evacuated, and replaced with the preservative. The chemicals then penetrate deep into the wood. You can't dip or paint wood and get even close to the same protection. Let's start at the very bottom. Put in a proper foundation.
Concrete pilings are the best, extended up to ground level, under each support.
No termite pre-treatment necessary. The builder comes in with a giant post hole digger, drills holes in the ground and fills the holes with concrete. Build up from that, using aluminum heel plates between the concrete pilings and wooden supports. These plates will keep the joist or girder ends above the earth and moisture. While we're still at the bottom, let's consider something else.