Too and too much

Too is an adverb. It can modify verbs, adjectives and other adverbs.

Too has a negative meaning. It means ‘more than is necessary or desirable’.

She is too fat.
The water is too cold.
It is too late.

We can use an infinitive structure after too +adjective / adverb / determiner.

He is too old to work.
We arrived too late to have dinner.

All expressions which modify comparative adjectives and adverbs can be used to modify too. Examples are: much, a lot, far, a little, a bit, rather

She is far too young to live on her own.
You are a little too confident.
It happened a bit too soon.
He is much too old to work.

Too much cannot be used before adverbs and before adjectives without nouns.

He arrived too late. (NOT He arrived too much late.)
He is too old to work. (NOT He is too much old to work.)

Cases where too is not used

Too is not normally used before adjective + noun.

She doesn’t like men who are too short. (NOT She doesn’t like too short men.)
I couldn’t solve the problem – it was too difficult. (NOT I couldn’t solve the too difficult problem.)