Step 1:
https://sellercentral.amazon.com/learn/ref=xx_su_dnav_xx

Step 2:
https://sellercentral.amazon.com/product-search?ref=xx_catadd_dnav_xx

I assume you are setup as an Amazon Seller and not just to use Amazon Pay.

Have you been through Amazon’s Seller University? https://sellercentral.amazon.com/learn

Amazon Pay is a different product than an Amazon Seller’s Account

Become an Amazon Seller

Because all Sellers are immediately suspended for Seller Identification Verification Do not click the “Sign Up” button on the top of the page. Instead scroll down to the link title “Sign up to become an individual seller” https://sellercentral.amazon.com/gp/flex/sign-in-syh.html?ref_=sdus_soa_hp_ri_pf&ld=NSBing_SDRI_HP_PF_SWM_T1

This will save you from paying $39.99 each month during verification. You may upgrade to the Professional with the monthly fee at anytime later after you have completed the Verification process.