I'm scared because price Bitcoin down, I do not know what to do with Bitcoin at this time

if you are scared of the possibility that bitcoin might drop again , so why don't you convert your bitcoin into fiat right now . actually you don't have to be scared about that because you are in an investment aren't you ? and because you're in an investment you should understand the risk of having your money in bitcoin . all you need to do is to be prepared of what will happen in the next few months and just expect the unexpected .