Right sift key is backing browser to previous page.

I don't think this is a hardware issue. What browser are you using, and does this problem occur in all browsers?

It's possible that (if you're using Firefox) your mouse or trackpad isn't working as it should. Thus, SHIFT + Scroll functions as the browser's back or forward buttons, so that's why you would be experiencing this. To remedy this:

1.) Type about:config in the Firefox address bar and press Enter.
2.) Search for the preference "mousewheel.with_shift.action" excluding the quotations.
3.) Double click it and change its value to 0. (source)

I did it but it wont work, and i am facing this issue in Crome as well as mozilla and microsoft edge also.
but in word file and else key is functioning normally.