Your first step in using AMPL/Gurobi is to download the appropriate distribution for your platform: 64-bit Windows distribution
amplgurobi9.1.2_linux64.tgz: 64-bit Linux distribution
amplgurobi9.1.2_mac64.tgz: 64-bit macOS distribution

For Windows users, choose a destination directory folder. Virtually any folder will work such as C:\AMPL or C:\Program Files\AMPL. Then copy the distribution to the destination folder and extract the contents by unzipping it.

For Linux or Mac users, choose a destination directory, such as /opt/ampl or /usr/ampl, then copy the distribution to the destination directory and extract the contents. Extraction is done with the following command:

tar xvfz amplgurobi9.1.2_{linux64,mac64}.tgz

After the contents are extracted, you should open doc/index.html and readme files, which provide instructions for activating license and completing installation, and user guide.