Utthita Trikoṇāsana: utthita = extended; trikona = three angle or triangle
Triangle pose stands in line with Plank and Tree poses to build strength in legs and start developing balancing skills. If you are a beginner, you will practice it often in your yoga class. Although it may seem doable, there are some key points to pay attention to.
How to get into it? check this: https://inshape.blog/yoga/poses-and-asanas/triangle-pose-trikonasana/