Spiderman beats Cap 6/10.
When they fought in Civil War, Cap had been fighting alongside Spiderman for weeks. Cap has videos where he watched spiderman fight, he even said he studied his fighting style in the civil war saga. Thats why when cap threw his shield, he knew where spiderman would end up, so that cap could launch a volley of punches. As far as how powerful those punches would be, cap obviously couldn't be sure, but it didn't take him long to figure out how to box spiderman out. Spiderman is too reliant on his spidersense, which is something cap knows.
However, given caps' relative strength, speed, agility, to spiderman, vs overall fighting ability, and skills. spiderman wins. In their fights spiderman hardly ever used his webbing to web cap, which is very CIS. If he had, cap, who is a very quick character, would have been slowed down, if not imobilized, rending the fight over.
Cap has chances, however, against spiderman, he loses more times than not.
As for cap vs spiderman damage wise? most of caps hits from bricks against his shield. Which, with its vibranium alloy absorbs most of the impact. Cap rarely takes blows full on, he deflects, or dodges most blows, cause if he did take them... well you saw what spiderman did to cap.
P.S. I want iron man to die a horrible painful gruesome death for causing the eventual death of captain america. in which his armor repeatedly gives him an rectal probe for the rest of his life.