This is the 3rd most frequent Russian word.
с
The Russian word "с" means "with" or "from" depending on context.
In this sentence, 'с' indicates accompaniment, showing togetherness or association with someone.
Я иду в парк с друзьями.
I am going to the park with friends.
'с' here introduces the activity or event with which something begins or is associated.
Он начал свой день с зарядки.
He started his day with exercise.
In this case, 'с' denotes the circumstances or conditions under which the action takes place.