4(1/4+1/5)+4 i need to see step by step to be able to understand the process pls

You should use PEMDAS for this, which determines the order of operations:
P = Parentheses 
E = Exponents
M = Multiplication
D = Division
A = Addition
S = Subtraction

1. So your first step is to solve the part in the Parentheses:
1/4 + 1/5 = ?
The lowest common denominator of the fractions is 20, so transform both fractions so that the bottom number is 20. That means for 1/4, multiply both the top and bottom by 5. For 1/5, multiply both the top and bottom by 4:
5/20 + 4/20 = 9/20

Therefore you now have 4(9/20) + 4

2. Then the next step is multiplication. Multiply 4 x 9/20.
4 * 9/20 = 36/20 = 9/5 = 1

Now you have: 1 + 4

3. Then do the addition.
1 + 4 = 5