Your pup sounds much like mine around that age. He is now a bit over 3 yrs, more tolerant of adult humans (I am absolutely not going to risk a child to work on Woolf's behavior), still hates all dogs except for our other dog, but has learned to ignore them for the most part. He is managed. It took finally finding the right behaviorist/trainer and training of some kind every day to reach this point. If kids had been in the house and involved, there is no way I could have worked with Woolf and gotten to this point, it wouldn't have been safe for the kids.
If you are up to the time and commitment required, a trainer and/or behaviorist should be located. Keep in mind it isn't a quick or a cheap fix. You still may not get the results you want, you may instead find yourself compromising to keep your dog and others safe.
The other option is rehoming, which does have it's pitfalls as well. Rescues are overloaded. It would be difficult to find one willing to take on a reactive pup. If you gave him to another family, there is the risk he could become more unstable and actually bite. It would have to be a verified experienced home if you chose that method.
The first step I took with Woolf was a full checkup with bloodwork, then found the behaviorist we work with (after a couple of side trips with trainers who didn't know/understand what was needed). Did the evaluation, then made some decisions. There may or may not be a charge for the eval. There was a charge for Woolf's but it was a very involved and lengthy process.
If you will post where you are located, someone may have a good recommendation for you.