Sorry for the really delayed response, it's hard to keep up with comments at times.
Yeah - you are changing your keys on your account. It's "forever" until you decide to change it to something else.
can i create another account with eos voter?
Yes, it's under Tools -> Create Account. It requires an existing account to create (and pay for RAM) for the new account.
to have another public and private key, how can i do that?
Yep! Tools -> Key Generator will let you generate an unlimited number of new key pairs.
so i just follow those steps and its done? create a new account with my existing account and then create a new keypair. Do you have a tutorial i can reach to? im not really tech savy as you may notice haha