should you use the ordinary BHA/AHA red mask if you use tretinoin everyday?

its tretinoin as a spot treatment or for whole your face ? aha bha peeling used by 2-3days/week , depend of your skintype and condition . IMO u should skip the tretinoin when using aha bha red mask to avoid irritation or sting feeling .

You definitely can. Just use it in your morning routine probably once or twice a week as long as your skin can tolerate it.

You can, but my recommendation is to skip tret altogether that day. Otherwise you can irritate your skin which can lead to further issues.