It depends on the situation: food contact materials themselves do not require FDA "registration," but they must comply with the relevant provisions of 21 CFR, and Amazon will require an FDA compliance statement or test report; if the product is food/dietary supplements/cosmetics, FDA establishment registration is required. The testing cycle is generally 10–30 working days, and the cost is 1,000–40,000 RMB. The Shuwang Testing and Certification Platform can provide document pre-review and compliance pathway assessment; see https://www.shuwangtc.com for details.
Common misconception: confusing "FDA registration" with "FDA testing." For food contact materials, the focus is on migration testing and ingredient compliance; cosmetics involve MoCRA (the 2022 new cosmetics regulatory rules) facility registration. The official original text shall prevail.