Water surface using Modifiers (Ocean & Wave)
The pool floor is just a plane with textures
Inflatable Float created using the base cube(but subdivided), put through basic cloth simulation with the woman and the watermelon as collision objects
Monokini was a quick one using Marvelous Designer
Hat - https://skfb.ly/otwSq
Watermelon - https://skfb.ly/o7Qy6