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
Reach streamer rank 1
Upgrade ASMR to max level
Draw 10 times
Upgrade Dance to max level
Upgrade Draw to max level
Upgrade Jumping Jacks to max level
Upgrade Squats to max level
Reach 5000 viewers
Get 1000 subs
Do Jumping Jacks 10 times
Buy 6 zones
End 10 streamings
Buy 10 bikinis
Buy 5 bikinis
Do squats 10 times
Do ASMR 1 time
Buy 3 zones
Get 500 subs
Reach 1000 viewers
Dance 1 time
Pop 10 extra viewers bubbles
Get 100 subs
Reach 500 viewers
Draw 1 time
Buy 1 zone
Get 20 subs
Do Jumping Jacks 1 time
End 1 streaming
Buy 1 bikini
Pop 1 extra viewers bubble
Reach 100 viewers
Do squats 1 time