Generally, you don't directly modify the toolpath in Fusion. What sort of changes are you interested in making?
Jeff
Edit in tool path like changing the tools and depth of cut and sequence of tools.
Perhaps I am mistaken, but from your last response, it sounds like you may benefit greatly by working through the tutorials. There is a wealth of information out there:
Mike Mattera's written tutorials: https://forums.autodesk.com/t5/fusion-360-computer-aided/if-you-re-new-to-fusion-cam-try-this/td-p/6...
Lars Christensen Youtube channel (search for CAM): https://www.youtube.com/user/cadcamstuff
John Saunders Youtube channel: https://www.youtube.com/user/saunixcomp
And of course, this forum. If you get stuck on something in particular, by all means, come to the forum and ask. Provide specifics as needed: part file, pictures, Screencasts etc