This is a simple rotating indicator that slips over the neck of my inexpensive water bottle.  The cap keeps the pointer on the number simply with friction.  When I refill my bottle, I move the pointer to easily keep track of how many times I've refilled my water bottle.

The opening fits over the threads of my water bottle (63mm) and the counter fits snuggly over the body of my water bottle (73mm).  The gap between the lid and the body on my bottle provides the friction to keep the pointer on the number (2mm).  I haven't mastered parametric modeling but it shouldn't be too hard to adjust the dimensions to fit your water bottle.

Designed in TinkerCAD.
Printed on my Elegoo Centauri Carbon using 0.12 layer height, 4 walls in Sunlu PLA+2.0 white and red filament.   Supports were used on the number ring.  The pointer was "flipped" so no supports are needed on it.