First of all, sticking your own trademark on someone else's product is definitely infringement, unless it is approved by the manufacturer of the product.

Secondly, a registered trademark can be declared in the name of an individual, but only if it is an individual industrial and commercial household and provides a copy of its business license.

Finally, no product can apply for a trademark first, but the scope of the trademark must be consistent with the business scope in the business license.

If you have any questions, please feel free to call me at Baidu HI.