There is three main security cam programs , I use two of them.
MotionEye OS and Pikrellcam.
MotionEye OS can use USB webcams.
I use old secondhand Sony Playstation 2 Eyecams.
Can get them as low as $2.
Good for bots and they have 4 microphones
Pikrellcam uses the Pi camera which costs more but are 8M pixel.
But it can use the Eyecam as audio input for motion movie capture.
I am seriously wanting to understand all of this...but I think it may take some time .
Yep, been using them for 7 years and I still barely understand them.
If you are scared of learning then perhaps give that old Pi away and get a life
I think Eben said in the blog video the other day, no one person can know it all.
He said something like 300 people were involved in developing the new Pi4.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges