Have an AI walk you thru setting up Home Assistant, which is often considered the best software for doing this (and it’s probably free). What you want is totally doable and done by many people as a little tech hobby and helpful upgrade to the home stuff. It’s not super hard, but having an AI be your mentor will make it much easier. Project cost might be a few hundred dollars, since you will want a cheap mini computer and a few electronic bits to allow communication between various devices. Of course, the individual devices e.g. nice phillips hue lights, are all additional costs.

You could also check out the HomeAssistant subreddit, but it’s often a bit technical and not focused on someone starting out like you are.