What can I do for my son who is scared of water?pa

Help! , Im in desperate need some good advice. My 7 year old son is DEATHLY terrified of the water. Earlier last year, my husband and I spent thousands of dollars taking our 2 boys to a indoor waterpark retreat and was basically just a huge waste of money, the water makes both of my boys super nervous, my 12 year old -not so much as my 7 yr old, I cant even give him a bath without him constantly “needing a towel” to dry his face if even a little drop of water hits it. Ive tried calmly talking to him about it, and showing him that its okay, its not going to hurt him, i’ve tried explaining to him theres already “water” (tears) in his eyes constantly. While we were at the waterpark, he had a life jacket on while we were in the wavepool (waves were NOT active at the time) and my husband tried to let him go to show him that everything was okay and he wasnt going to go under the water… he screamed bloodly ell out of terror and starting hysterically crying… well, at that point, my mother instint set in and I immediately went over to comfort him and tell him he was okay… he latched onto me so tight and locked his body around me and wouldnt let go. I took him and sat him on the side and after calming him down, I tried to ground him, i had him observe everyone around him and get him to realize that everyone in the water is OK and are having fun. He didnt want any part of it. I finally got him to be okay with going into the lazy river with me (which was packed full of people) and some young girl behind us wasnt paying attention and ended up placing her huge intertube over his head and knocking him almost completely off his tube… well he started screaming and crying “that girl just tried to kill me!!” … so needless to say the most recent experiences in the water for him have been somewhat traumatic. He is deathly afraid of drowning and not being able to breath under water and terrified of water getting in his eyes. I don’t understand where this is coming from, I loved the water since I was young and even competed with my school swim team back in middle school. Heres the dilemma, it’s important to my husband and I that our children know how to swim, it could save his life. We love the water and want our children to be able to enjoy it along with us. My husband tells me we need to just put a life jacket on him and just let him go … let him scream and cry in terror until he realizes that he is okay … he tells me not to come running to him when this happens, to give him the time he needs to adjust. When he told our son what the plan was he started crying and became extremely anxious. I dont want my son to go through that though. I understand he has to face his fears but there has to be a better way to do this without further traumatizing him. I thought we should start off with a kiddie pool with only a few feet of water and allowing him and his brother to play, for me, that would be a better first step and much less traumatic… but where would I go from there? Idk, im at a loss rn. Any suggestions and advice is greatly needed and appreciated. Thanks.