I am kinda new in this cryptocurrency and i wanted to buy some altcoins but i don't know which one, my friend said i should buy neo but i am not quite sure if it is a good coin or not.
It depends on what result you are expecting.
If you want just to purchase some altcoin and then (in some time) sell it and get profit, you should purchase BTC. It`s the most profitable coin so far.
If you want to support some projects with interesting ideas, you may choose any that you like. But it may be not as profitable as you want.