I applied on the REI portal.
After passing that hurdle, I was given an online video test (of sorts) with HireVue. This wasn't as bad as it sounds. You're asked questions, you respond into your computer or phone camera, and if you don't like your answer, you can re-do it, maybe twice. I think there were less than 5 questions. They are the typical behavioral questions. "Tell me about a time when you were faced with..." or, "What is good customer service to you?" You can look these up elsewhere, get familiar with these kinds of questions, they will help you in any interview.
After passing that, I had a videochat interview with the store's hiring manager. I think the acid test here is that if you know REI, and have a genuine passion for the great outdoors, plus an interest in sharing that with others, you have a good chance of being hired. If you don't, there's no use in faking it, the manager will likely spot it out. This counts for far more than product knowledge.