My best advice is to set up two separate areas, one for your older dog where he can get away from the puppy - adults won't attack a puppy normally, unless pushed to far, but puppies have no respect/fear of older dogs and will push and push - and one for your puppy (recommend a crate).
If you have your older dog's bed in a room, with a baby gate across so they can see each other without the older dog feeling threatened, and be mugged when he wants to take a nap, this will avoid confrontations.
The message is be there for your older dog. Once he knows you are going to 'defend' him, he'll settle down. If you don't, he will growl, probably, and if pushed, may well bite. You need to avoid it deteriorating to this point. And feed them separately for now too. Food is a trigger. Obviously they need to have time together, to form the bond, but only under your supervision to start with. If you have to do something else, crate the puppy/put your older dog in his separate area.
You do realise this BC/Whippet mix is going to be a high-speed nightmare don't you! Having gone through baby Whippet myself, that was eye watering enough at times without adding the high energy BC into the mix. Not something I'd remotely entertain, apart from the fact there's nothing 'wrong' with either breed, on it's own. I guess it's too late to persuade you otherwise, but I would suggest you need to think very carefully about what you are about to take on. Might look cute now, but by 10 months, you'll have, potentially, a hooligan on your hands.