dear simona
i understand your condition
ok then for these two years you have to cover your each topics related to class 11th and 12th
dond bouther about your facility etc.
just have faith on you
start with ncert
practice each & every question given in it and have the inprin of the book in your mind
something like you can flash the book from your eyes
then go for any refresher like comprehensive(chem) hc verma(physics) & rd sharma(maths)
meanwhile keep on knowing iit related informations
just complete these books & you will understand the whole way