1937oldfart :
I have a cd downloaded from MS, can I use this to upgrade my laptop that is running win7 prem, without loosing any data?
1. probably.
2. Anytime you do a major upgrade like that, expect the worst.
You absolutely need a good backup of, at the very least, your personal docs.
What if the upgrade goes wrong? Or your laptop runs out of power partway through? Or any one of a million other fail modes.
You cannot assume that it will all go perfectly. It probably will, but maybe not.