Hi...I am using iphone4 that is ios7.1.2 . Now want a update that is ios 9 or high. Please help me

Not possible, an iPhone 4 can not run any version of IOS higher than 7.1.2. You will need ti buy a new phone for anything higher than that.

Your iPhone is using the highest version of iOS that it supports. It can't be updated beyond that. You'll need to buy a newer model phone if you need to use a newer version of iOS.