Can’t connect

• What is your model Apple TV?
• What is your model MacBook?
• What are you trying to AirPlay? Some services may be blocked for AirPlay.

How to AirPlay video and mirror your device's screen - Apple Support

If AirPlay or screen mirroring isn’t working on your device - Apple Support

Stream content using AirPlay with Apple TV - Apple Support

Some home networks are set up to use either the 2.4 GHz band or 5 GHz band for Wi-Fi by using separate network names (SSID) for those bands. That would create two distinct networks that can’t talk to each other, including AirPlay. Verify that both bands are bridged as one logical network.

AirPlay has an on|off switch on the Apple TV, as well as settings who is allowed to AirPlay to it. Verify those settings.

Do you have Home Sharing turned on for both devices and verified they are using the same network and AppleID?

https://support.apple.com/en-us/HT202190 and also https://support.apple.com/guide/tv/stream-content-to-apple-tv-atvbc876df1e/tvos