The count can vary significantly. I have about 150 Processes running via Task Manager.
(Side bar: Interesting - a bit higher than what I expected so I am going to go back later and take a closer look....)_
Overall though, I do not pay that much attention to the physical count per se. Windows is always doing all sorts of things and what is what is difficult to determine.
Use the Status %'s to identify named processes that may be taking, using, demanding high % values. Click the column headers to sort the results in descending order.
Resource Monitor will do much the same.
People are often tempted to just kill some process that appears to be an issue. May not end well....
If some process seems to be dominating resources...