What to study for a simple home automation scheme?

Question

linux

I want to slowly start building something like this:
1. Video surveillance in the apartment, which reacts to movement and sends a signal in any way. The apartment is rarely visited.
2. Screwing the system to this video camera so that a certain action is performed if this motion sensor (which notifies me) is triggered - for example, turning off the power in some device, let it be a working PC installed in this apartment (turned on). You can just break the power supply, it doesn't matter.
Actually everything to start.
Tell me where to look, what to choose, what to study?
From languages, software - Bash, python? Are there any frameworks, blanks?
What to choose from iron, Arduino, Pi?
What else is useful in this case? Thanks for all the comments.

Answer 1

Creating a video surveillance system using motion
This seems to be exactly what you need.