Uninstall And Re-Install Of Parallels Questions, Please

Hello,

In my 80's now, so please bear with me a bit.

Trying to Un-Install all of Parallels, and then Re-Install it. Have a relatively new iMac.
Major problem is the incredibly slow speed when on the Windows 10 side.

Have followed all of the instructions, I think, in the various KB instruction sheets
that address doing this. But:

The Parallels Icon in the upper menu bar in now gone.
The two Dock icons on the Mac side for Parallels Desktop, and for Windows 10 are now also gone.

a. But I cannot remove the Parallels Desktop icon in the Mac's APP Folder.
Tried dragging to trash, etc.
Nothing works.

b. Is this important when I try to re-install, or should it be removed, now, prior to the re-install ?
If so, how please ? What am I, as usual, missing ?

c, Also, the Mac is now trying to re-install Windows 10.
This is before I have tried any Parallels re-install.
Why is it doing this ?
Should i allow it, or must the W10 re-install be done during the Parallels re-install ?

If you could specifically comment on (a), (b), and (c) would be most appreciative.

Irrespective of the well written KB instructions, I would be very grateful
on specific instructions on how to do the Un-Install and Re-Install of Parallels, tailored
a bit for my comprehension ability now.

Much thanks, really appreciate the help,
Bob