Fusion 360 does not have an Marlin/MPCNC post processor file in it’s default configuration so you will need to download the one initiated by WorkerDrone and tell Fusion 360 to use it. Try my slightly modified version attached here.
OK – here is my attempt at some bullets for you:
* Download and unzip the attached MPCNC_Fusion360_V2_RTH.zip to a convenient folder.
* In Fusion 360:
* Generate tool paths and simulate
* Select tool path or paths
* Select Post Process
* In Configuration Folder section select Setup and browse to your convenient folder
* In Post Configuration section select Open Config and select MPCNC_Fusion360_V2_RTH.cps
* Select an output file location and name
* Select Post
Please let me know if anything is unclear or wrong.