Originally Posted by ace2153
Can twrp be flashed before root is that safe ?
Yes, it is safe but you will have to flash recovery with Odin. Read "Option 1" on the How To Root guide:
It shows you how to flash recovery with Odin first and then to use the recovery to install root.
Once you have your recovery installed, you can backup your existing ROM and then just flash a new rooted ROM if that is what you want to do.