How do i know which verbs have or don't have an "s" by the present 3rd person?

Question

For instance:
he likes
he sleeps
he goes

Answer 1

It is always nesassary to put "s" after verbs in present forms of 3rd person!

Answer 2

I can't think of any but in Elizabethan and medieval England the suffix 'th' was often used instead. Example 'My cup runneth over.' Much of Shakespeare's work was so written. 'Methinks he protesteth too much.'