How does TLD DNS server find the specific authoritative nameserver containing required information?

Considering this article, DNS Server Types, by Cloudflare, there is a TLD nameserver that is responsible for finding the authoritative DNS server containing the required record. But how does the TLD nameserver know what are the authoritative DNS servers so it can search in them? Imagine I want to start a domain name registering company. How can I register my nameservers in the TLD server so it will know to include my server in its search?

A TLD nameserver is not responsible for finding anything externally.
It is responsible for answering queries with referral information specifying the authoritative nameservers for the requested names based on the information that it already has.

Eg, the com nameservers, when queried about foo.example.com will send a referral response containing information about the authoritative nameservers for example.com, all based on information that already exists in the com zone data.

In practice, the information about the authoritative nameservers for example.com were fed to the com nameservers with a flow outlined below:
Registrant → registrar → registry → delegation in the TLD zone

Ie, the registrant (customer) purchases and manages their domain name through the registrar, the registrar has a business relationship with the registry (essentially owner of the TLD) and sends the information for the domain there (as well as part of the money they took from the customer), the registry puts the relevant records for the delegation into the TLD zone.