Should I use a dynamic microphone or a condenser microphone for recording a podcast? What about streaming on twitch or making youtube videos? Should I ever use a ribbon microphone?
The most important factor when deciding on a microphone is the environment where you will be recording. Each microphone technology was developed for a certain kind of environment.

Condenser microphones like the Blue Yeti are designed to record their entire environment with the utmost clarity. If your environment is noisy then the microphone audio will be noisy. But if the environment has been acoustically treated then the recording will sound detailed and clear. 

Dynamic microphones like the Shure SM7B are designed to record sounds spoken within a 18 inches of the front of the microphone. All other sounds will be quieter and less detailed. If the environment is noisy then the microphone audio will tend to mute out sound that comes from off-axis. If the environment is quiet then the audio will sound good, but only if the person or instrument being recorded is within 18 inches of the microphone.

A ribbon microphone is designed to capture extremely loud percussion sounds, usually from drums or brass instruments. They are not suitable for recording human voices as they tend to emphasize frequencies not usually associated with the human voice.