Numbers are the basic building blocks of mathematics. They each represent a value, or an amount. So if I have a single banana it means I have 1 banana. But if I have two bananas, a pair of them, that means I have 2.
0 - Name = Zero. Value = None, nothing.
1 - Name = One. Value = Single, one units/object.
2 - Name = Two. Value = Double, two units/objects.
3 - Name = Three. Value = Triple, three units/objects.
4 - Name = Four. Value = Four units/objects.
5 - Name = Five. Value = Five units/objects.
6 - Name = Six. Value = Six units/objects.
7 - Name = Seven. Value = Seven units/objects.
8 - Name = Eight. Value = Eight units/objects.
9 - Name = Nine. Value = Nine units/objects.
10 - Ten.
20 - Twenty.
30 - Thirty.
40 - Forty.
50 - Fifty.
60 - Sixty.
70 - Seventy.
80 - Eighty.
90 - Ninety.
Numbers continue infinitely. The only limit is your computer, mind or drawing space for you to write numbers.
The 100's(hundreds), 1,000's(thousands), 10,000's(tens of thousands), 100,000's(hundreds of thousands) and even 1,000,000's(millions) are used somewhat commonly today.
We're entering a world where billions and even trillions are used due to inflation or computer bit and byte memory or network transfer capabilities.