Belgique,
I am not sure from your description what the end configuration you want to look like.
The short answer is most things are possible, not all solutions though are practical (due to extra components and or cost).
So I get you want to have a camera at the gate, and you want to see it in the house, lets expand on this detail.
1) Do you want to look at the gate camera from
a) Computer's in your house
b) Televisions in your house
c) dedicated monitor (s) in your house
d) all of the above
2) Have you already purchased the camera, and if so, what are the details
3) Please provide some more details on the screens you have, particularly in relation to question 1.
4) What cabling do you have in place
a) in your house
b) to the gate location for the camera