"I will not watch too much TV."
Translation:No veré mucha televisión.
You are right, kenaxo, and it is interesting that in English the ambiguity is only in the negative. "I didn't put in too much sugar" can mean "I only put in a little sugar" or "I didn't put in more sugar than I should have [i.e. not more than the recipe called for]". In the affirmative only the latter meaning is possible ("I put in more than I should have," but not "I put in a lot.")
Having said that, it is very common in some parts of Africa for speakers of English to use the affirmative "too much" to mean "a lot": "I like football too much!"
In a single clause you can have only one conjugated verb (in this case voy/am) and the other verbs have to be infinitive or participle forms. You have conjugated the first verb to va, which translates as "he/she is going", and your second verb, veré, is also a conjugation, meaning "I will see". It doesn't make much sense when you try to put them together.
Also you have to use demasiada here, since it's an adjective that refers to the feminine noun televisión.
It should be "No voy a ver demasiada televisión" - "I am not going to watch too much TV."