I dont know when

Question

to open curly braces({ ) and when to close it ( }) any suggestion will b helpful

Answer 1

to execute set of commands/statements together accn to evaluation of particualr condn ... then its better to put all in { }
//as without brackets only 1 statement will be included by default
//for () ... generally used to pass arguments for a method [inside ( )]

Answer 2

{...()...()...}

Answer 3

At the start or end of a: Class, method, if statement, elae statement, else if statement or loop if any kind.