As long as you can stand in a pool and get yourself back to upright if you slip you should be fine.
Places that do baby swimming will keep the the shallow end (or the pool in general will be shallow). Just tell the instructor you arent confident in water and keep to the shallower end as much as you can.
In the one we go to the shallow end is about hip height on most people.
If you slip are you able to get back up and of the water. The pool that I took mine is one depth and it's all chest height. I would speak to the instructor before you start the lessons and tell them you can't swim.
As long as you can stand in a pool and get yourself back to upright if you slip you should be fine. Places that do baby swimming will keep the the shallow end (or the pool in general will be shallow). Just tell the instructor you arent confident in water and keep to the shallower end as much as you can. In the one we go to the shallow end is about hip height on most people.