Yes, but you must use "been" after "have".
Student or Learner
You have watching TV too much.
You have watching TV too long.
Do we use much or long if someone spending too much time in watching TV.
Or You have been watching too much TV.
Or, in general, you watch too much TV.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
Yeah, you are watching too much TV.
"You have been watching TV for too long" is correct if you mean at one sitting.
A person might not watch too much TV in general, but if they are watching TV for 7 hours straight, you might consider that "too long".