#1
I just put on new strings chnageing from flat to rounds. When I put them I did adjust everything cut them just right and everything tuned up and the and the a string buzzes around the 2nd and 1st fret and I didn't happeb on the old strings any suggesstion to fix
#2
Does it buzz when you hit and open string or is it when you fret the first or second frets?

If its an open string its probably your nut

If its on the 1st and 2nd fret it could still be the nut or it could be worn frets.

How old is the guitar? Newer guitars don't generally have fret issues unless really crappy small fretwire was used, but nut problems can happen to any guitar. I have the feeling you probably wore the nut down a bit more (happens) then the round strings can handle and the string is getting placed too close to the frets near the nut.

Remedy: Replace nut or frets as required and have the guitar setup again.

Hope this helps, Cheers!
#3
When you say you adjusted everything do you include the Truss Rod? Often flatwounds are stiffer or a higher gauge than rounds. So some adjustment of the Truss Rod might be needed.

Also, I think flatties are known for getting less fret buzz, so where you might not have heard it on the flatties, it might have been there and you're only now hearing it on the rounds.

There are loads of sources online that will help you to check your neck relief, or lack of it. Worth looking at before you spend money on replacing anything.