what to do with "gullak" money

i recently broke my last 8~9years of savings made by regularly depositing any money i got from relatives and the all the money i received on my birthday . it accumulated to 21k as 1st year student with a already new laptop and negligible expenditure . i really want to save it and invest it in the best possible way . i already have a demat account but any decision made on the money would have to be approved by my parents so nothing to extreme like day trading can be carried out with it .

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