It’s often quite informal and fairly short (10–30 minutes) for this kind of entry-level role. Sometimes there is a group stage first (you might be in a room with several other candidates) before being asked to do one-to-one questions. Glassdoor

Interview was around 2.5 hours in total. Started with a group interview then 20 minutes on the shop floor shadowing a checkout colleague then finally a 1 to 1 interview with a manager.