May someone explain to me how to do this in the easiest way? i don't really understand. ❤

Make the whole into 5/5 then subtract the numerators

Well in order to subtract fractions you must first get a common denominator. the reason for this is because of if we have
1 - 1/5

and we do
1/1 - 1/5 (notice how 1/1 = 1 so it is ok to do that)

if we did this and subtracted numerator we would get 1 - 1 = 0 and denominator would be 1 -5 = -4. So 0/-4 = 0. We we know that is not the answer because only 1 - 1 can equal 0. also we can check it by saying the fraction 1/5 = 0.2. and so 1 - 0.2 = 0.8. So so we can clearly see the real answer.

now watch as I use common denominator.
1 = 1/1 = 5/5 ( notice 5/5 = 1 so it is ok)

So so we can plug in 5/5 for 1
5/5 - 1/5

subtract numerator
5 - 1 = 4

the denominator will always stay the same when doing addition and subtraction. So so the answer is:
4/5

We can check this with what we did easier and see that:
4/5 = 0.8

there are other ways to look at it. You have been using common denominator since you learned addition and subtraction. every whole number like 1 or 2 or 3 or 4 have a common denominator of 1. You you just were not taught that. watch this
4 - 2 = 2 or
4/1 - 2/1 = 2/1

and we know 2/1 is 2
This this can be done with all whole numbers. If you can remember this then you can always understand common deno minators.

please let me known If this helped you understand. i like to hear feedback or maybe I can try another explanation