I should replace every single switch with a smart one to do that. Which kind of switches do you have? If they are Wi-Fi how do you avoid hitting the max number of devices your home router is able to handle?
Either the switches, or, usually easier, the bulbs. As sibling said, Zigbee, but there is also Z-Wave (z-Wave is bigger in the USA, stricter. Zigbee, bigger in Europe, is more open, but you can get devices that suck in some way if you do no research). There is some new thing that’s related, Thread/Matter something, but I didn’t look into that yet.
ZigBee is the contemporary standard du jour for this stuff. Wifi is fine for some things but doesn't offer the same benefits (e.g. implicit mesh network of devices)
