Cr@p swimmers R Us. Great thread, get on board.
I'm a complete noob to this game too. I could swim 25m crawl after a fashion but was knack'd by the end of it. Then I could do another. By signing up with the local tri club and getting proper coaching, plus regular visits midweek to the pool I've moved ahead. I've got a fairly lightweight upper body mass so can't just add more power to overcome inefficiencies. My last pool swim was 2000m in 54 minutes. It's not a brag because that's quite slow, but I was only at the 25m stage in May this year. As Alibear says, zero to 800m in about 8 sessions, not all of those were coached. Once you get the hang of the timing it gets a lot easier.
The more you do it, the more like second nature it becomes and the less you have to think. One of the biggest single factors was the leg movement., ie primarily using the thighs to simply elevate the body in the water, rather than trying to "kick". (Try to breath air, too. That helps)