433Mhz RF Signal copy

Hi everyone,
I am starting now with arduino on a domotic project for my house. I have electric gates on my property, which they have 433Mhz remote controls, and i want to replicate the open/close signal, so that i can have a arduino uno with a wifishield and xbee or other RF Transmitter, to open/close my gates by internet through my phone. My questions are:

is it possible to connect wifi and a RF transmitter to the same arduino board?

how can i copy the signal of the original gate remote control?

thanks in advance!

is it possible to connect wifi and a RF transmitter to the same arduino board?

Yes, it is.

how can i copy the signal of the original gate remote control?

You'd need to know something about what is transmitted. Is it binary data, ASCII data, or just a specific frequency?

the remote I have opens/closes the garage gates, I don't know what information is actually transmited, that is my problem, how can I know ?

You need to know more about what the remote transmits.
You need to know the modulation type, could be AM or FM and the data format.
There is no easy way to simply copy or duplicate the signal.
The other option is to simply use the Arduino to simulate the pushing of the
button on the remote, which will require you to disassemble the remote.

which will require you to disassemble the remote.

Not necessarily. Double-sided tape to hold it in place, and a servo to press the switch…