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