Nevermind, I figured it out. I did it like this just in case anyone else is interested. Just change the IP address of your opengarage.
sensor:
- platform: rest
resource: http://192.168.1.111/jc
name: attic temp
value_template: '{{ value_json.temp }}'
unit_of_measurement: '°C'
- platform: rest
resource: http://192.168.1.111/jc
name: attic humidity
value_template: '{{ value_json.humid }}'
unit_of_measurement: '%'