Infrared with Arduino Uno

I would like to ask, how to use arduino to make a remote control that using infrared?
1. Is it the frequency of IR should buy in same pair TX and RX?
2. What coding should I use?

Buy a 38KHz receiver. It's a 3 pin receiver. The transmitter will be configured to run at 38KHz using software.
For code, you can use an IR library(check the google) or do it the hard way lol

Adafruit has also a good tutorial on it's website.
these IR receivers come for different carrier waves, 36KHz, 37KHz, 38KHz.
There are some different major IR protocols, if you want copy a certain one, it all depends what you want.