make two curves similar as a parameter changes

Hello everyone, I have a question not exactly simple to ask you.

I have an .xlsx file whose data I cannot upload as it is sensitive data.

Within this file I have created two scatter graphs using respectively for each two columns having a very high number of rows.

The values ​​relating to the x axis of the second graph are arctan values ​​that vary as a parameter X varies; I was asked to make the two curves as similar as possible, that is to make the second curve (the one relating to the arctan) follow the trend of the first. To do this I would have to vary the value of the parameter that multiplies the arctan.

How can I solve this problem?

I hope I was clear, in case you need it I will attach a sample file.