How to route cables outside?

I would like to have a network cable hanging out at the roof overhang on all 4 corners of our new building to be able to install surveillance cameras there via POE (without additional power).
Preferably duplex, so I can cover all areas with 8 cameras.

Do I need to use a special outdoor cable - are there duplex ones?
Is a regular Cat7 installation cable sufficient, where I then crimp an RJ45 connector on?
I would prefer not to install network sockets outside everywhere to use a patch cable...

A network cable should also be laid in the shed of the carport - should a conduit be used as protective coating for underground cables?

Does anyone have an idea how to implement this most sensibly?

I would not leave a cable hanging at the corners of the house but rather lay an empty conduit there. This way, you are more flexible regarding the required cable. Even if a bad guy cuts the cables, even if the cameras are mounted a bit higher, it could still happen that someone gets the idea and follows through with it. In such a case, it is easier to lay a new cable.

An underground cable does not require a protective conduit. However, it is not wrong to include a tape or something else as a warning above the line so that during later digging, one is alerted early enough that there is a cable running there.

Of course, a protective conduit is not bad in that case. If a conduit is laid, it is not necessarily required to use an underground cable; you could also use a normal cable.