Win10 forces update but on restart restores old version and repeats

Hi
1.

I just want to wipe it out and start with fresh windows 10 but I don't have a disc

Windows 10 iso's are freely downloadable - details in the Tutorial section or via search for 'media creation tool'

2. "Could not find the recovery environment: insert your windows installation or recovery media" - suggests either you've lost the Recovery partition or it's disabled or some other corruption has occurred. (It is possible to reinstate a lost Recovery partition, test if it exists and is enabled, and enable it).

If you are happy to reinstall Win 10, that may be the simplest way to go. However note that if your build is 1709 or older, you would be installing the new 1803 build; it sounds as if it's trying to upgrade to that and failing.

(Which build? Windows key + R, winver).

I suggest, given the possible corruption, that you check your disk before clean installing.

Before clean installing, make sure you have all data backed up.

Download Windows 10 ISO File | Windows 10 Tutorials
Create Bootable USB Flash Drive to Install Windows 10 | Windows 10 Tutorials
(or simply burn a DVD if you have a DVD drive)
Clean Install Windows 10 | Windows 10 Tutorials

Finally, as ever, once your PC is working, start using disk imaging routinely to protect your PC, your data and perhaps your sanity- giving you a relatively quick way to recover to a previous working state without technical help- even if your disk fails. E.g. Macrium Reflect (free) + large external storage.

Note: the update isn't 'forced' - if you have Home, you get updates and upgrades delivered. That's the product you bought (not that I agree with the way MS does this at all!). If you pay for Pro, you have more control.