can I give my rooster a bath inside during the winter
Oh that's good. I would think you can bathe him in that case. Chickens generally don't like getting wet so it's probably a good idea to wash him in a sink so the water can drain as you clean him off. A second person to help hold him might be good. I have had good luck using salves and ointments to close wounds on chickens since it's so hard to keep bandages on them. I recall we used to have some kind of copper based powder for the goats to stop bleeding, but I can't remember what it was called.
Have you been able to stop the bleeding? You can use cornstarch or flour to help stop the flow.
Get the blood washed off. Use a blow dryer and dry him thoroughly.
You can apply something like vetericyn to the comb then dab a little bluekote on the wound, that will help disguise it so hopefully the others won't pick at it.