The open hi hats can be seen in the sheet music where the hi hat has a circle around it.
All the beats have open hi hats on the “and” of the beat (i.e. 1 + 2 + 3 + 4 +).
These beats are a good introduction to playing open hi hats in general, and particularly good for learning the off best feel. These beats need to be repeated a lot and groove needs to be felt by the drummer. A simple ska type guitar riff accompaniment would be an appropiate jamming style for developing an internal sense of groove. On bass a fun slap and pop bass riff would fit, or else something funky without these techniques.
Related: For more of a challenge, try these: Open Hi Hat Grooves Practice Piece with Fills