Окончание s добавляется только к глаголам третьего лица, единственного числа в Present Simple (он/она/оно - he/she/it)
Я, ты, мы, вы, они - окончание s не ставится.
I like it.
We like it.
They like it.
You like it.
She likeS it.
He likeS it.
It likes it.