Data loss from I cloud while erasing the old i phone.

i am planning to give away my old i phone to my brother. Before doing that i would like to erase all the data on it, all the data from my Old I Phone has been backed up on I cloud. If i just erase my I phone will it simultaneously erase the data on I Cloud also ?

definitely my objective is to keep all the data from my Old I phone on I cloud so that i can access it from new I phone..

please help !!

cheers

Nik