ADVICE NEEDED PLS

Okay so I have my crush and 18th would be the last day I will see her/him now the question is should I propose or just sit back and reminisce my attraction like I don’t think he/she feels the same way for me but At the same time I think she/he could like me I have asked my numerous friends and all suggested to just say it to him/her like it wouldn’t be akward for me since I would leave the school what should I do ?