IWTL how to stop daydreaming?

So, I have realized(around a month ago) that daydreaming has ruined my life(I am a student so there is not much life). I have been trying to stop doing it since the last week with no success. This(daydreaming) is interfering/causing problems in my studies and general day to day tasks too. Like I am doing something I must do, then I start daydreaming and then 10 minutes later I am doing nothing, my motivation to do that task is gone. I don't think that is relevant but most of my daydreams are about me being successful(This is some stuff I never wanted to share with anyone but just understand how tired I am with all this that I am posting it here). It is kind of ironic but daydreaming is what is stopping me from doing anything productive to be successful. P.S: this is not my main account for obvious reasons. And you can get the level of daydreaming by this that I started daydreaming that you people will help me and I will stop daydreaming etc etc. I am fcked