This is a paid asset, but now you can download Hamburger Menu Free.
Detail this asset from Unity Store: Original Link
Hamburger Menu v1.0
“If possible, please buy the package to support the developer”
Hamburger menu is an extension of Unity’s scroll rect component. Reacting to mobile and mouse input, sliding in and out of view, this off-canvas Menu reacts just like a native mobile menu.
– Dynamic scaling
– Mobile & standalone
– Nested scroll rect
– Easy to modify
– Mouse/mobile input
– Portrait & Landscape
– Quick setup
– Works with Screen Space – Overlay/Camera & World space render modes
– Source code