I have a 3 month year old baby rat help on introducing to adult rats?

Try and put your bully rat outside of sages cage. See if sages comes to the door to interact or minds her own buissness. If rats want to cuddle, or interact they go to the other rat. If they are scared they will stay away and mind their own buissness. Gradually see what happens. You could also put a bowl of food between them and see if they are willing to share, or if one wants it all for themselves. Hope i could help!!!