Only keyboards with piano synth capability
or actual pianos (acoustic or electric)have
SUSTAIN pedal input.
The two basic pedal on a piano are Sustain originally called 'Sostenuto' by the Italian inventor & Damper (originally called 'Una Corda).
The sustain pedal stops the individual key dampers (which stop the strings vibrating) from returning to the strings hence sustaining the sound until the pedal is released or the string stops vibrating. For full use of the pedal look at some older piano music in semi-clasical vein. You will find under the staff the sign Ped._____* The 'Ped' indicates step on the pedal, the line is 'hold'and '*'indicates release pedal. Probably some use could be made of sustain in using guitar sounds but for the most part it is for Piano sounds. Organs, strings & wind instruments don't have sustain (i.e. the sound doesn't carry after the note is stopped). As far as the damper pedal on a piano, it reduces the volume of sound only. On pianos with three pedals, I think the middle one is the clutch, but it's not required with the new automatic transmissions.

The middle one is Sostenuto. I allows to hold the notes while playing new notes that are NOT sustained. But a clutch would be good too.
DonM