One of the hardest things for most photographers to learn is how to control a photo shoot and direct people from behind their camera. It is why for a lot of people they end up turning to landscape photography or shooting random candid portraits either with long lenses or portraits that are obviously posed and stiff.
I always try to keep in mind this quote from Robert Cappa when shooting portraits, ““If your pictures aren’t good enough, you’re not close enough.” The traditional approach to shooting portraits is to use between a 70 and 105 mm lens to shoot a portrait, but I have found that 80% of my portraits are shot with a 50 mm lens or wider. By using a wider lens it does two things to my portraits. One, it forces me to be closer to my subjects and interact with them on a more intimate level. Two, it allows me to include more of the environment or location that we are shooting in. Since I am rarely shooting in a studio, I find that by including the environment in the portraits helps to tell a story about the person.
True shooting portraits in a studio can be a lot easier, since you have total control of the environment, but I find that the portraits I do on location always seem more alive and vibrant.