Upgrading and old ffmpeg version to the latest on redhat

Currently I'm on a new project and working with an existing server (redhat) that has already been setup. One of my tasks right now is to upgrade ffmpeg to the latest version. I'm familiar with navigating the shell and all, but I'm not too familiar with how to upgrade software. So far I have the following down:

• Typing the ffmpeg command I can get the version number (2.6402)
• Doing a which ffmpeg shows me that the command is being run from (/usr/local/bin/ffmpeg)

I then download the new updated release from: https://ffmpeg.org/download.html#releases -- And I read the Install.md file:

• I'm afraid to type the install commands as I don't want to overwrite my existing ffmpeg version as I didn't back it up in case if it doesnt work well. Or does the ./compile and make install only happen in the current directory only?

• How do I backup my existing ffmpeg in case I need to revert it back?

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