Another noob question: see the attached image of my thermostat. Would it be possible to switch it for a smart one? What would I have to check? If it is possible, what would you recommend? If is don't want any 3rd party app or account?
You're going to hampered in your choices by the lack of wires. You have an old 2 wire setup. Most nowadays want 3. Some can handle 2 wires, look for thermostats that don't need a "c wire" or "control wire".