Here is the full list of all 36 Hot Tub Simulator achievements.
Pop 100 extra viewers bubbles
Do ASMR 10 times
Dance 10 times
Draw 10 times
End 50 streamings
Do Jumping Jacks 10 times
Do squats 10 times
Reach streamer rank 1
Buy 6 zones
Upgrade ASMR to max level
Upgrade Dance to max level
End 10 streamings
Buy 3 zones
Upgrade Jumping Jacks to max level
Upgrade Draw to max level
Upgrade Squats to max level
Dance 1 time
Do Jumping Jacks 1 time
Draw 1 time
Get 1000 subs
Buy 10 bikinis
Buy 5 bikinis
Pop 10 extra viewers bubbles
Reach 5000 viewers
Get 500 subs
Do ASMR 1 time
Get 100 subs
Reach 1000 viewers
Do squats 1 time
Buy 1 zone
End 1 streaming
Get 20 subs
Reach 500 viewers
Buy 1 bikini
Reach 100 viewers
Pop 1 extra viewers bubble