Target image size is equal to source image size, so that is ok. Forget about ppi that is only there to confuse you.
I suppose with good quality you mean the artifacts that are introduced and visible on the right hand preview. That is a standard jpeg issue. The art is to keep those as low as necessary. The higher the quality parameter the less these artifacts are the bigger your file gets in storage size. For the web that means transfer time from the sever over a slow line to the user’s computer.
And don’t forget: Jpeg compression is lossy and the issue is cumulative for each generation. So only the final image should be saved as jpeg and an original should be kept as Photoshop file or tiff file (if there are layers) or png file (additionally with no layers). There are still other considerations but this should do to start with.