Hello,
probably my problem is easily solvable for many of you, however I have not been working with R Studio for long and need some help.

Here is my problem:
I have two columns of a relatively large data set. The first is the retail price and the second is the sale price. Now I want to compare these two columns and know by how many percent the sales price is higher than the manufacturer price in each case.
Since the dataset has a lot of numbers to compare and R studio probably can't give me the percentage change for each case, it would be helpful if there were percentage ranges.
For example, in 200 cases there was an increase between 50% and 100%, 140 cases with an increase between 100% and 150% and so on.

I am grateful for any tips and thank you in advance.

I fully agree with the given advice to provide a reprex, but I also like to point you to section 20.4.3 Scalars and recycling rules which explains how R is capable of vectorised operations.

The example given below contains 1.000.000 records and calculates per case the price and percentage difference.