If you look in the command editor, it is Under the command description > Access control. If you mean editing/adding them through chat, then: !addcmd <cmd> %<level> <message> (Here are the different levels: 1. All viewers; 2. All VIP; 3. All VIP + Mods; 4. VIP Silver + VIP Gold; 5. VIP Silver + VIP Gold + Mods; 6. VIP Gold; 7. VIP Gold + Mods; 8. Mod Only; 9. Bot & Streamer Only.)
Example: !addcmd !level %8 Commad Message Input Here