Differin

Yes it's possible to use it everyday. Going from twice a week to everyday might be a bit extreme though. Perhaps try every other day for the next couple weeks

Yes you can but you need to gradually increase the usage so that your skin barrier won't be damaged. You don't wanna over exfoliate your skin and you need to be patient with the result. Built up the skin tolerance in a slow pace.

Yes as long as your skin can tolerate it... It is very good of you to start it slow but u should increase the frequency of using differing in a week so your skin can become much more stimulated and healthier... Btw I use different brand of adapalene everyday during night and it is fine for me :)

You can start increasing your use slowly and supplementing your skin with a lot of soothing and hydrating ingredients. I use Epiduo which is also an Adapalene, and these products work for me well to keep everything hydrated. This will save you From a damaged skin barrier. Don’t forget to use sunblock, especially now since Adapalene increases sun sensitivity.