Hello...so I have a new place and wanted to get rid of the old chair rail molding on drywall. Naturally when I removed it there are 2 distinct lines of layers of paint that had been used over the years. I have tried sanding them down to the point they feel smooth yet after a first coat of paint you can still see them. I tried a bit of spackle but of course even after sanding and painting that area has a different texture compared to the rest of the wall. SO my question is how can I get rid of these lines so when I paint they will be as unnoticable as possible. I saw some videos on drywall mudding and taping but then read mud wont stick to paint. Any suggestions would be appreciated