After (Prep) meaning later than something, or following another event in time. This form is used in front of a noun phrase.
- We’ll leave after they call.
- They lost contact after their grandmother’s death.
Later (Adv) Meaning after the time of speaking
- See you later!
Later (Adj) Meaning after something else or in the future or an advance period of something.
- The taxi arrived an hour later than expected.
- The concert has been postponed to a later date.
- She wrote her most interesting poems in her later life.
Afterwards ( is used when referring to an action followed by another one.
- We went out to dinner and afterwards we went to the theatre.