The USAF only bombs third world countries with limited or absent air defence. They have never gone up against a peer or near peer nation. Russia flies over Ukraine but they can do most of what they need to do with missiles, drones and guided arty. This is an attrition war-it’s the slow grind that wins it.
No, they can’t do what they COULD do with their numbers. That is, if the RuAF were capable of SEAD. If they had that capability they could break any army.
The RuAF currently cannot interdict worth squat. It can’t prevent resupply and reinforcement from Poland, nor the logistics of any Ukrainian front, nor movement of forces between fronts.
US doctrine is to create aerial supremacy over enemy territory. The USAF and USN are equipped with a vast range of capabilities and doctrine to suppress enemy air defenses (SEAD). If it comes to a conventional war with the USAF and the USN engaged vs Russia they will certainly attempt to do that on Day 1.