Hi,
This is a very broad topic, so not entirely sure how far we will get, but lets see what we can do.
Is that message displayed when you plug your mobile phone into your computer via USB each time?
Assuming so, perhaps consider starting here:
I would recommend looking within Device Manager and see if there is anything that it doesn’t recognise and uninstall it first.
I have the same phone and when I plug mine in it is recognised and within Explorer it will appear as an icon of the phone and a drive letter will be assigned to it.
If I double-click on it I can then explore the phone, however, if the phone is locked I need to enter my pin in order for this to be updated.
I honestly can’t remember whether I needed to install anything specifically for my phone (I’m using Windows 10), but I believe I did install something which enabled me to transfer files, maybe Smart Switch or something similarly named, chances are if this was the case that may have installed the relevant USB support I needed if it wasn’t already present in Windows 10.