I looove tret, but I do have to point out that the beginning is kind of tough! You will most likely go through a period where your skin will break out, be extra sensitive, and you'll not like what you see every morning, buuut once that period is over - just super amazing skin!
When starting, I would recommend really simplifying your skincare - single cleanse, hydrating toner, tret at night/vitamin c in the morning, moisturize, sunscreen during the day. I would stop any physical exfoliating and pause any BHAs you're using. Avoid applying near your mouth area as the skin will get super dry and flakey.
They also make two forms or tret - cream and gel. The cream is easier to spread and is more hydrating (in its own way), while the gel is great for more oily skin, but wow does it absorb super fast. You can also start with a low concentration while your skin adjusts.
Some people use a sandwich method to help with dryness and irritation - lightweight moisturizer, wait ~10 minutes, tret, wait another 10-20 minutes, heavier moisturizer.