is 'vien' necessarily followed by de

Bonjour Diana,

It depends on what you're trying to say. When you mean "to come from" or "to have just done something," yes.

I'm coming from a restaurant - Je viens d'un restaurant.

I just ate - Je viens de manger.

But in other contexts, you could simply use "venir" on its own:

I'm coming to see you - Je viens te voir.

He's coming to my house - Il vient chez moi.

etc...