While external noises can be removed from the recording after it is complete, this will diminish the overall quality and level of detail in the audio file. You'll get much better results if you put up some basic soundproofing before you start. A basement makes an excellent recording studios as much of the traffic and wind noise from outside will be muffled. Or, choose a room in the middle of a building that doesn't have any windows that open onto the street. Hanging heavy rugs and carpets on the walls can also help absorb sound a little.
Your voice recording will improve if you set up some isolation inside the recording room. Sounds can bounce off the walls and be detected by the microphone. These early reflections produce high-frequency buzzing sounds on your recording. Hang soundproofing foam, rugs or curtains on the interior walls to help deaden them, giving you a cleaner end result.
Run your microphone into a compressor before connecting it to your recording equipment to compress the audio on the way into the system. The dynamic changes in volume will be leveled out, giving a volume closer to the average overall level. This will allow you to drive the gain more, giving you a louder signal with less background noise. You can always apply additional compression during post-production, but recording with some subtle compression on the input channel helps give you predictable dynamic structure to work with.
Equalizers allow you to cut and boost frequencies across a frequency band much wider than the human voice. This means that much of the spectrum is unused by the recording, allowing unwanted noise and background interference to creep in. Set a high pass filter that cuts off the lower part of the frequency band. Turn up the gain control until some of the vocal bass starts to disappear, back it off again so the vocal itself is unaffected. Create a low-pass filter and roll down from the top end, removing any high-frequency background noise. The actual recording should not be affected by these filters, but they will help create additional "air" and "space" around the vocal.