There are open and closed categories on Amazon. Closed categories means that not every new seller can directly enter and sell products that require a license. Unauthorized categories are called closed categories. To sell in these categories, you can send the licenses and documents required by that category, get approval from Amazon, and open that category to sell. An example of a closed category is the food category. After obtaining an FDA license to sell in the food category, you can open that category and sell your product.
But which categories allow anyone to sell a product without asking for any documents.
Among them:
Baby
New & Used Books (New & Used Books - Collection Books Excluded)
Camera & Photo (Camera & Photo)
Consumer Electronics
Fine Art (Art - new seller registration is limited)
Home & Garden
Kindle Accessories
Musical Instruments
Office Products
Outdoors
Personal Computers
Pet Supplies
Software
Sports
Tools & Home Improvement Toys (Toys)
Video Games
Let's not forget that the competition in the closed category is much less than the competition in the open category. The competition in the open category is very high.