Now let’s talk distance. If your arms are proportional to your body, a good rule of thumb is having your knees line up with the edge of the piano. This provides a comfortable reach.
If your arms are longer or shorter than average, just look for this shape when you sit – arms beside, but not touching the torso, a gentle bend in the elbows, with arms flat-parallel to the keys.
Basically what you want to avoid is sitting too close, which causes the elbows to jut out, the wrists to drop, and making it impossible to use the pedals when you eventually get to that. Or, sitting too far away, with no bend in the elbow, causing a lot of strain in your arms.