Open Package Manager, located under Windows drop-down
Under the Add(+) package option, choose Add package from disk
Locate the path where you downloaded the package
Select the package.json file located inside one of the package's directories.
Installation from a Git URL (Unity v2019+)
Open Package Manager, located under Windows drop-down
Under the Add(+) package option, choose Add package from git url
Paste the git url for the package you intend to install inside the box provided, such as: https://github.com/ebukaracer/pkg-name.git or https://github.com/ebukaracer/pkg-name.git#xyz
