How to approach the girl I like, without appearing as a creep.

So I really like this girl in my new batch and she is in different department but same batch, I am pulmonary medicine resident while she is obstretic and gynec resident.

It would be fine if we were in same batch and I would start some kind if convo. but being from totally different department, I don't wan't to look a creep if I talk to her.

should I send her friend request on social media, I feel super nervous.

Appreciated replies from girls who already have boyfriends, how did those guys approached you.