300DT alternator/water pump belt??

[siral3x]

So my water pump/alt belt is loose and cracked. I have been puting it off bc it's the low 10s outisde and don't have a garage. However I need to get this done bc I'm planing to go on a longer trip.
The guys at Autozone said it's only 1 belt...howerver my eyes tell me that there are 2 skinny belts!?
Is there a tensioner? or any tips on how to get the old ones off easily??
Thanks in advance