请帮我看看我这句英文对吗？

office room最好不要简单翻译成房间，翻译成（您的）办公室会比较好一点。其他的没错。
你的办公室在5楼102。这是门卡。

Your office is Room No. 102 at 5F. The card is an access card

your room/office is at 5F,room number 102,this is the ID card.

Your office room is No.102 at 5F.This is your access card.