[Altavia]

If unable to follow the instructions, maybe these will help.

Honeywell Smart WiFi Thermostat - Setup and use - YouTube

Honeywell Home WI-FI Smart Color Thermostat(New Model)! Unboxed Reviewed & Install😊 Smarthome Must - YouTube

One of the wires probably needs to provide continuous power but may not be connected in an older home. So may need a HVAC person to help with that.