Do NOT key up (talk) immediately when you join a new channel. Listen for 2-3 minutes to understand the etiquette, topic, and active users. "Keying up" without listening is considered rude and will get you banned.
Before diving into directories, understand what makes a channel tick: zello channel directory
Remember: On Zello, you are never alone—there is always a channel waiting for your voice. Do NOT key up (talk) immediately when you join a new channel
Many valuable channels are private or "semi-open," requiring a password. Directories often (with admin permission) list the password or instructions for requesting access. zello channel directory