I have an english bull terrier, my friend has a ***** in season. Any advice is very needed!!!?

He is getting on a bit and i would rather keep our bullies as one family. Both dogs are beautiful. But we arent sure on what needs to be done. How to tell that 'the job' has been done and that shes up the dufff. How to change dietary needs and look after the *****, and what signs to look for in changes of my male.