There aren't many cars for sale.
A Lot Of
Use a lot of with countable and uncountable nouns:
I need a lot of tools for my job.
Does your car need a lot of oil?
The man has a lot of cars.
Many
Use many with countable nouns:
He has many friends.
Are there many customers in the store?
The house doesn't have many rooms.
Much
Unlock full access by logging in. Registered users can explore the entire lesson and more.