Nouns include egotist or narcissist. The adjectives would be egotistic, narcissistic, self-absorbed, or selfish. Basically a person like this will be always be alone, insecure, and unhappy with their life, unless they change. Usually friends, family and others find a person like this to be annoying and weak, if all they do is talk about themselves constantly.
selfish
"Story" is a synonym that starts with "s" for news.
substantial
The synonym is "saluted" in the sense of applauding an action.
Sailor is a synonym for mariner.
sailor, shipmate, seafarer
synonym
savor
"Scout out" is a synonym for "check out" that starts with 's' and has the 'ou' sound.
Spear is a synonym for lance. It begins with the letter S.
scope ?
scene, sign
A synonym for cannabis that starts with S is sinsemilla.