@joebristol
If your club is anything like mine, don’t worry about getting better before you turn up to a swim. They will normally run a lane system for different levels.
Some one else pointed out here try and get as much open water swimming in as you can. You would be surprised how many competent pool swimmers panic in open water. Also cold water is something I struggle with. A warm lake in Austria I am fine, sea swim in Weymouth and I can really struggle to get my breath and get into a rhythm. Sometimes I manage it (tenby) and I have a great swim other times (malorca) I really struggled to get my face in the water in the cold and breath properly.
My friend went from a non swimmer to 70.3 Ironman in two years and Ironman in 3
Also yes swimming is a technique sport but don’t get 100% hung up on it. For years I thought I was missing the one thing that would turn my swimming around. Like most things, doing a lot of it will improve. Most triathletes are never going to swim like someone who swam for a swimming club since they were 10.
Once you do get reasonable though you will hate swimming in a public pool, even as a moderate swimmer everyone will be in your way 🙂
As for breast stroke yes some people do it, but its more fatiguing on the legs than front crawl. Just put the effort in and learn to swim crawl and you will be in a better place and you will feel proud of yourself.