Bird box questions

Make sure the bird box is at least 6 ft above ground level on a wall that a cat cannot climb.

Don't put them in trees, as cats can get to them easily there.

Don't have a landing perch on them, as the magpies will be able to get at the young then.

Yes, a camera is a good way of keeping track on the birds in the nesting box.

Don't place the box in direct sunlight, as it can get so warm the chicks die if you do.

If you really want to see the chicks as they hatch and grow in the nestbox, you could buy a nestbox with a camera or webcam attached. Some of them have a wire connecting them to your PC or your TV, so that you can eavesdrop at any time, and others (the more expensive ones) send photos and videos wirelessly to your PC or mobile. Look online - there are plenty to choose from. Be aware that the cheapest of them have poor quality pictures and are not very reliable.

You might be better (simpler and cheaper) to find someone else's online webcam to watch. Here are some examples.
www.wildlifetrusts.org/webcams
birdcams.live/

Sorry, that was a little bit abrupt.
We watch our boxes and are aware when ours have fledged. We then empty them and give them a clean ready for the next lot so if there are any parasites they are not passed onto the next brood.
We aren’t bothered about watching them in the box but it’s very entertaining watching the parents and , if we are lucky, we see them set off into the big wide world.

Put a hinge on the lid.

Maybe if you left it alone and stopped checking it, the birds would feel safe enough to use it?
You shouldn’t have removed it and looked for eggs, what if there had been chicks in there?
The bird boxes are for the birds to use, and for you to watch from a distance.
Just put the box out of the reach of cats,
and Leave It Alone.