Hi Doglover1234
Where have you tried to get your dog to swim? The best place is somewhere outdoors with a body of water that does not have waves (so not an ocean) and the dog can walk in gradually. Kiddie pools, bathtubs, etc. don't work well because of this. A lake, pond, or pool with long steps into a shallow end is best. Streams can work well too.
If you have already tried a lake/pond/pool/stream, try it again but go in there yourself. This will encourage the dog to follow, and also let him see that the depth is reasonable. Depth perception through water can be a problem for both people and dogs. I encouraged my dog to get further in by floating a piece of kibble on the water, and he got used to 'dunking' his nose to get it.
It goes without saying that you shouldn't allow anyone to pull, push, or throw your dog into the water as this will give him a bad experience he doesn't need.
HTH!