There is a hardware menu button on the Note 3, but in order to access an apps menu you have to navigate through the hardware menu to get to what you need. Not only is it an extra step it can be a pain. Developer PsychicJian has created a solution for this problem. His "TreDots" mod adds an overlay 3 dot menu to any app screen so that you no longer have to navigate through the hardware menu. This mod does require that you be rooted, and that you have a custom recovery installed. You will download 3 files. You will then replace a particular file with one of those three files using a file explorer. You will then flash the other two files inside recovery. Then just restart your device and enjoy. Head to the link below for the full instructions and files.
via XDA