I was reading the difference between the two, and in the example of TCP:
For example, when a user running a Web browser requests a page, the browser uses HTTP to send a request via TCP to the Web server. When the Web server receives the request, it uses HTTP to send the requested Web page back to the browser, again via TCP.
Example of UDP:
The best-known Application layer protocol that uses UDP is DNS, the Domain Name System. When an application needs to access a domain name such as www.dummies.com, DNS sends a UDP packet to a DNS server to look up the domain. When the server finds the domain, it returns the domain's IP address in another UDP packet.
Which of the two happens initially? How does connection to a website happens in the end?