How to arrange files in desired order in Finder in macOS Catalina ?

I want my files to be particular order in finder for that I'm using, 'sort by > name'

But I tried renaming in many patterns but I'm not getting my desired order

here is screenshot of my finder window

In this you can see order is shown by Mac is

Episode 1

Episode 2

Episode 3.5

Episode 3.25

Episode 3.75

Episode 3

Episode 4

But I want it in following order

Episode 1

Episode 2

Episode 3

Episode 3.25

Episode 3.5

Episode 3.75

Episode 4

I tried many combination but Ep3 always come after all sub episodes of 3 and in sub order 3.5 always come before 3.25

Is there any way to customise this order of files ?