It is probably bolted or cemented to the foundation.

Why is this a concern? Is it the ascetics?
There is no "product" to fix it. Dig it up or live with it. If the house was built after the Johnson administration, it's unlikely there is any form of mechanical attachment.
Ron

As Dick Nixon said: "I am not a crook(ed window well)."

Well, thanks for the responses. I assumed the window well was somehow attached to the concrete basement wall on the outside. If it's not, then digging and levelling would do the trick. Guess I thought there might be a window well extension, but when the first 5 pages of a Google search indicate otherwise, I must learn to trust. The low side of the window well is at ground level, which of course is not good. And yes, it looks like Dick (Nixon).

Is the window well out of level or is the ground not level?

I have three crooked window wells. It's hard work but can and should be fixed.I dug the side that was lower and put it in place with a come along.instead of trying to re bolt, I just welded it then sealed it .

"It's hard work but can and should be fixed."

Why?

It is most likely strictly an appearance issue.