Typing in Cyrillic letters is relatively easy, each key on the keyboard corresponds to a different letter, like a standard English keyboard. However, there are multiple layouts for typing in different Cyrillic languages, as well as different layouts for the same language. Read more about the different Cyrillic keyboard layouts. If you are learning to type in Russian, you will most likely be using the default Windows Russian layout.
However, it can be difficult to type Cyrillic on a QWERTY keyboard until you have memorized the location of all the Cyrillic letters. While learning to type in a Slavic language it may be helpful to buy pre-printed, pre-cut stickers to put on your keyboard's keys to remember which QWERTY keys correspond to which Cyrillic letter. These are widely availble online, and are inexpensive.