@NervousSwimmer
You can do it! Good for you for even trying to conquer your fear.
My SIL is from Kenya and not much swimming done where he grew up. And when he did try it once, someone threw him in the pool...thereby terrifying him for life.
At 41 yrs old he conquered his fear! We rented accommodation for our family for my son's wedding. There was a small heated swimming pool in the back garden. SIL decided he wanted to try to learn to swim. I absolutely hate having water in my nose and eyes so I use a face mask. I let SIL try dunking his head in the water with the face mask on...he was standing in the swallow end..about a metre deep and just leaned over frontwards and was able to look in the water. He was thrilled. From there, he sat on the steps and held on to the side and then let his body naturally float. Once he realised that he had some control and wasn't going to sink, it wasn't long before he was swimming all over that pool under the water with his body completely submerged! The smile on his face when he came up from under the water was priceless! Everyone was very excited because it isn't every day, if ever, that you get to witness someone conquering a genuine terrifying fear.
I suggest you try using a face mask in the bathtub whilst sitting up and just leaning over to stick your face in a bit., if you have one available to you. Once you're comfortable with that, see if you can relax enough to let you arms float, then try with your legs.
I wouldn't do lessons until you are completely comfortable in the water at a pool. It is so much easier to swim under water and have fun, than to try and learn fancy swimming strokes. They are difficult to coordinate and aren't even necessary to enjoy swimming! Im assuming you're not going to go out for the Olympics swimming team, so just enjoy the feeling of being weightless under water and also enjoy the unbelievable quietness...it's another world under there!
Later, if you feel like it, you can take lessons to learn the fancy strokes.
You can do this@NervousSwimmer I drowned as a toddler, so I had to overcome my fear...and I did!
I've spent zillion of hours enjoying the water...not trying to win an Olympic medal...just playing around and having fun!
The nice thing about a face mask is that you can even attach a snorkel and practically never have to come up for air. I used to swim laps at the pool nonstop for 30 minutes at a time without every coming up for air..just using the snorkel.
Good luck! You've got this!