Windows 10 or Windows 11 Pro?
If I were in your shoes, I would first back up all my existing drivers. I will explain later why this is important.
Do a clean install of Windows using MCT (Media Creation Tool) offline. This will ensure no unwanted updates are installed on your computer.
Now restore all your drivers offline. Restoring your drivers online is not a good idea as it will also install all Windows backups including Bing, Copilot, etc on your pc.
Deactivate your Windows Security comprehensively. Now install an antivirus-software with a small footprint online. I have been using Avast One for years. This is of course a personal choice.
Following that, install Revo Uninstaller Pro to uninstall any unnecessary Windows program. Generally these are the only apps you need to keep.
Next up, install all your applications and configure them to your liking. Use a good system cleaner such as BleachBit or Privazer Pro to clean up your OS. I take for granted you are running an SSD. That means you don't need a defragmentation tool.
Just put on Windows Explorer, right-click C: Drive -> Properties -> Tools -> Optimize -> Optimize Drive C:
Finally back up your OS with a system image backup on your external drive with the software of your choice. Don't forget the validation process.
Doing a fresh install takes up more time. But you only need to do it just once and it will serve you for years to come.
If you need more help, just holler.