[KWo]

The box PC You are paying for renting it it's Your dedicated server. You are running the CS on it and You have all settings there for the user access (for example podbot.cfg in addons\podbot folder and the section about passwords; users.ini for AMX X in addons\amxmodx\configs folder).
To manage CS during the game You need to connect from another PC (in this case it's more thank likely Your home's PC). Any PC using data shared by the server is called a "client". So on the client PC (Your home PC You are trying to connect the rented dedicated server from) in folder ...SteamApps\counter-strike\cstrike or ...SteamApps\condition zero\czero You should have the file called autoexec.cfg (if it doesn't exist - just create it by notepad - it's a txt file). If You have everything there and You still have troubles with access to "pb menu" or "amx_pbmenu" command, open the file config.cfg (placed in the same folder) and find the same lines in it like in autoexec.cfg You wrote. If they didn't come there, just add them manually by notepad (config.cfg should contain "setinfo" lines with passwords You want to send to the server to get the access on it after joining it).