If your pet knocks over everything that comes his way, it's probably to get your attention. Felines have a highly developed predatory instinct.
Don't argue with him when he drops something. Create more play time with him and more cuddle time. Enrich his environment with occupation games and spend time with. him (2 x 10 minutes of play per day). If you still want to keep your belongings on the shelves, there are some little tips to teach your cat to behave better.