How do make grass move from birds eye view

Moving grass is just a specific type of turbulent noise due to how the wind gusts cause small vortices and wavefronts. ergo a valid approach would be to experiment with Turbulent Displace and otehr animated displacments, assuming you're really talking about top-down drone footage for instance. Other angles might require different treatment, but your blanket generic bullet point style post is really too vague to delve into any specifics...

Mylenium