Create a temperature sensor for Netatmo Thermostat and Radiator Valves

Copy and adapt (for your entities) the following code in your configuration.yaml under the sensor section.

- platform: template
  sensors:
     woonkamer_temperatuur_netatmo:
         friendly_name: Woonkamer temperatuur
         unit_of_measurement: '°C'
         value_template: "{{ state_attr('climate.woonkamer_2', 'current_temperature') }}"

The sensor name woonkamer_temperatuur_netatmo has to be unique for each sensor you define.
Change the climate.woonkamer_2 in the entity you find in your home assistant entities list.

Then in the lovelace layout insert a sensor card and look for the sensor name you specified earlier.