In my house, the local authority adult support services screwed a long vertical handle into the wall side of the bath. This was excellent for me, and also served perfectly for hanging things like dripping swimming costumes etc, when necessary.
I do have a walk in shower in my en-suite , but do like and need to have a bath. Just had my guest bathroom re-done and have purchased for myself a handle that clamps onto the bath which gives me support both with climing in and out of bath.
I use the system of turning over onto my knees to get out of the bath, then can use this handle to help me stand up and give me support when stepping out of bath.