There can be a huge number of reasons for that. If your computer has USB 3 ports you might try purchasing an inexpensive NVMe SSD (256GB are about $30) and an external enclosure which are about $15.
Then download a Windows 11 ISO directly from Microsoft
https://www.microsoft.com/en-us/software-download/windows11
Then Download and use the portable version of RUFUS
https://rufus.ie/en/
Run RUFUS and select the Windows 11 ISO file you just downloaded. Then under Image Options choose Windows To Go. There are some check boxes that you can select and you should probably just select them all for the greatest compatibility and least amount of trouble.
This will put a clean and fresh install of the Windows operating system on your new NVME SSD. To use it you will have to go into your computers “BIOS” and enable booting up from USB. On most of my computers you just start hitting the escape key when you first power on the computer. Many manufacturers make you jump through other hoops so it may be easier to just type “Advanced Startup” in your Windows search box to get to your BIOS or actually UEFI to do this.
It will take a bit of time for Windows 11 to set itself up. After you do that the most time-consuming task left is typing “Windows Update” into your Windows search bar and taking all of the updates.
This will let you know what your computer is capable of with a clean install. Chances are your slow system has something to do with malware, or who knows what installed on your computer or some other type of misconfiguration. It will also give you a good way to get into your computer if your normal hard drive or system gets corrupted or stops working. You can also use this Windows To Go Drive on other computers, but it takes extra time to reconfigure itself when you use it on different computers. My clean Windows To Go disks typically take under a minute to boot up after they are connected to the same computer that you last used it on.
Thanks for your help. I may try some of that, but I don’t think I’m savvy enough about the subject to venture too far into the bios..