This repo stores every AppID and its name available on Steam as json, CSV, xml and MD table by grabbing the info from the SteamAPI.
https://api.steampowered.com/ISteamApps/GetAppList/v2/
You can get the output without using the script.
GitHub Actions checks daily for updates and posts them to this repo. So this list will always be up-to-date.
Simply download the script and run it.
wget https://raw.githubusercontent.com/dgibbs64/SteamCMD-AppID-List/master/steamcmd_appid.sh
chmod +x steamcmd_appid.sh
./steamcmd_appid.sh