Can I play Acro Bike if there's only one card left in my deck? And if so, do I put that one card into my hand or discard it, or do I get to choose?
You can play Acro Bike with only one card left in your deck; but you have to put it into your hand, you cannot discard it.
Source: TPCi Rules Team (2019-10-31)

Relevant cards

Note: All applicable cards may not be listed below.
SM7_123
SM7_123a
SM7_123a
SM7_178