So, this might seem a little silly!! And it's not something you can buy! BUT I think before you go, you should write down what your goals are and why you're doing them. That way, if things get difficult and you're really struggling, you can look at that and remember, oh yeah, this is why! :) And maybe that goal will change over time, that's totally okay!! Goals SHOULD change, because you'll reach them and then you need new ones!
And the other thing is ALSO something you can't buy (which I am SO NOT HELPFUL lolololol) but take with you all the love and support that your friends have for you. :)