It can be confusing.
You have never taken a yoga class and want to begin. So you start your Google search, and there they are, all types, styles, trends, and promises. So how do you choose?
Why do you want to try yoga?
Good question to ask yourself.
If you want to get a more fitness workout Ashtanga, Jivamukti, Power yoga, and Bikram & Hot yoga are probably going to give you that energy burn you are looking for. These classes can be very challenging so you want to be sure you start with their basic/beginner classes. Even if you are a very active person, yoga is unique in the way it challenges strength and range of motion. Start with something accessible and move your way up.
If you are looking to reduce stress while increasing your strength and range of motion you may want to consider Viniyoga, Iyengar, a beginner slow flow, or possibly an introductory Kundalini. These too, can challenge but are more oriented to modifications, individual needs, and tend to move more slowly.
If what you want is straight up stress reduction or relaxation try Restorative, Yoga Nidra, Mantra, Pranayama or Meditation class. These types of classes direct the individual inwards, investigating interoceptive skills, exploring the 5th limb of yoga (Pratyahara), calming of the sympathetic nervous system. These practices are where much of the research is for: improving immune system; reducing stress hormones; increasing skills of focused attention; and improving such conditions as General Anxiety Disorder (GAD) and mild to moderate depression, and Trauma.
Once you have determined what you are looking for, read the descriptions of the classes and, if the studio has a mission statement, check that it is in sync with what you are looking for. Give the studio a try but that means giving a few return trip to explore different teachers. So, you may want to see if they have a beginner special or a small package deal that lets you sample different classes.
And remember: Your body, Your practice, Your decision to stay or leave the room.