This is the first time I've written a note on the internet. I want to write about my story because I'd like to express a special milestone in my life which could help (change my life) <-- not sure about this meaning (doesn't make sense).
Last summer, my bestfriend and I have been selling (umbrellas) <-- (Not sure about the word you're trying to use) 
which is a favorite fruit for women and pregnant woman in particular. You may think it's not big money <-- try not to use 'you'. You can replace this sentence with "It may not seem to be that much money", but the money means a lot to us since its the first time I've ever received money for myself. (Don't really need to use however but you can) Our parents believed that our studies were a first priority and told us not to continue it. At that moment we felt really 'bored' <-- I don't think this is the term you're trying to use. (You can replace this word with angry, sad or disappointing)