I am not a teacher.
"noise" can be both countable and uncountable.
"don't make a noise"
"there is too much noise"
You can hear "a noise", and you can hear "two noises", but you can also say that a lot of noises together is noise.
Both of these can be correct, though they have slightly different meanings. The first means do not make a single sound. The second means dont make many sounds.
"the baby is sleeping. Don't make a noise."
"the baby is sleeping. Don't make noise."
- For Teachers