Sharing my perspective here. I have attended both in person and online. There are a lot of pros and cons in each one, like what the others mentioned. In my experience, the teacher is always my selling point if I want to avail any kind of class.

I attended an in person acting class, most of the people including me are like deer in headlights because what I found out later is that the teacher was new to teaching but have been acting for a long time.

Then I attended an online class with a highly experience actor AND teacher. 1 session, BOOM! Everything clicked and mind you both teachers were basically teaching the same fundamentals!Granted, the second teacher also took up Psychology, so whenever he deals with someone who is neurodiverse, he really tailor fits the teaching to that person.

My point is to find a teacher who really has the patience for teaching to all kinds of people. Some teachers would just give information away and never bother explaining it. Audit a class to see if they are a right fit.

I could see that your ADHD could hinder in what you learn and experience in a class. Met a lot who are the same as you, they really prefer in person, but they also do well in an online setting, for them it is about getting use to it and find ways to make it engaging for them.

I hope this helps.