i have adjustable parallel bars so I wonder how wide should I set them for best chest stimulation? I heard 30 inches is good.

im only 5 7 btw

i take a grip sth like 3-4 inches wider each side of shoulder width and flare elbows to the sides and push with a chest, squeeze hard . correct?

and second question - dips are my first chest exercise. so i wonder if say 10 pushups and few bodyweight dips (5-6) are a good start before main weighted sets? jsut to feel the movement. then add 80lbs and do worksets