When I was a child.

Not really a complete sentence...

I need to buy some sugare.

I had two cups of coffee yesterday.

I found asome hair in my soup.

Many cars.

Not a complete sentence...

Is there any sugare in the jar?

A few/ hHow manyuch tea wouldo you wantlike?

When I was a child.

This isn't a complete sentence

I need to buy some sugare.

I had two coffees yesterday.

I have some questions for you?.

Is there any sugare in the jar?

A few/ hHow manyuch tea do you want?

I need to buy some sugare.

I had twosome coffee yesterday.

Could also say “I had two coffees yesterday” but I think that’s a more casual/spoken term and not really grammatically correct. So for writing I’d stick with using “some” of “a lot of” in front of coffee

MThere are many cars.

I have some questions for you?.

The original sentence sounds a little like you’re questioning whether you have questions. But if you were to use the original sentence in a conversation or a situation with more context then it could still make sense to the other person since it kind of implies that you’re asking if you can ask the questions.
If you still want to write it as a question you could say “Can I ask you some questions?”

I need to have somea few cups of coffee.

“Some cups of coffee” doesn’t sound particularly natural to me but I’m not sure why or whether it’s acceptable grammar.

Is there any sugare in the jar?

Overall it was well written

A few/ hHow manyuch tea do you want?

Many is used with plural nouns (for example, “How many cups of tea do you want?” but tea isn’t plural.
I’m not entirely sure what you meant with the “A few/“ part so if possible could you clarify what you meant then I can try giving you some feedback.