Prime factorization is a method to write number as multiplication of prime numbers
Let’s take an example
24
24 = 2 × 2 × 2 × 3
Steps
The steps are

Divide the number by 2.
If it is divisible, continue dividing until we cannot further divide or until the number becomes 1  If number becomes 1, stop.
 If the number is not 1, keep on dividing by other prime numbers 3, 5, 7, 11…
 Stop when number becomes 1
12
12 = 2 × 2 × 3
16
16 = 2 × 2 × 2 × 2
324
324 = 2 × 2 × 3 × 3 × 3 × 3
3360
3360 = 2 × 2 × 2 × 2 × 2 × 3 × 5 × 7
Note :
In prime factorization, we only include prime numbers.
So, 1 and the number itself is not included in it