Configuring the noise gate and noise suppression filters within OBS are both great ways to eliminate or reduce background noise. When first setting this up, it will need a bit of tweaking. Once configured, your mic quality will improve greatly. If background noise is interfering with your broadcast from outside your building, you can look to soundproof your streaming space. This will prevent your equipment from capturing unwanted noise in the first place. Switching to a microphone with a cardioid polar pattern can also significantly reduce background sounds from noisy environments. Cardioid patterns are sensitive to sound coming in directly in front of the microphone and have no sensitivity from behind.