how many different coins i will buy for trading?
I don't think anyone here has telepathic abilities to know how many coins will you buy. is it good to buy and sell 1-6 different coins or just stick to 1 kind of coin?
If you buy and sell 1-6 different coins you won't have any but it is wise to spread funds and buy many coins 
what coin and what was the best coin that i can be hold for a long time that give me good profit. can i have your suggestion
Read. Research. Don't ask for investment advice on forum open to public. 
godbless and goodluck sir.