What is the name for compound CH2CH2CH3?

CH2CH2CH3 is NOT a compound name, but a 'Propyl' functional group , which would be attached to a larger molecule.

Propane is CH3-CH2-CH3

Propene is CH2=CH-CH3

Propyne is HC=C-CH3 ( A triple bond).

The CH2CH2CH2, is written as R-CH2CH2CH3 , the propyl functional group and 'R' the rest of the molecule.