I did an upgrade is it better doing a full clean in stall whats the difference thanks.

When you do a clean install you will have no leftovers from your previous version which may clutter up your disks or cause problems. So less junk and less risk of problems. Or to put it in your unpunctuated lingo: yes it is better less clutter and less problems there you go you're welcome.

Do i have to buy windows 10 to do a clean install.