dirsearch VS gau

I am new to Python. With the help of several users (thanks u/Diapolo10 and u/shiftybyte)I've been able to install Python and the dirsearch package. Dirsearch (https://github.com/maurosoria/dirsearch) allows for checking website paths with a wordlist. For example, I have a wordlist file with words like "dog", "cat", "bird", etc and I want to check the validity of those words as extensions on a website. Something like "example.com/bird", "example.com/cat", etc. I have a test wordlist in the same directory as dirsearch, but I am confused on how to proceed with the commands. I want to have it check my wordlist as extensions on the example.com website and then save output on if the webpath is valid or not. Just need a little bit of help.

DirSearch

Learn more about dirsearch here: https://github.com/maurosoria/dirsearch

Empowered with a list of all the exposed URLs in your organization, you can then set up a process to scan these using a number of web-focused Dynamic Application Security Testing (DAST) tools and scanners such as Zed Attack Proxy, dirsearch (Web path scanner), Aquatone, and Nikto2. The OWASP® Foundation maintains a full list of scanning tools that could be used.

Scan our domains and infrastructure to reveal if we have exposed.git repositories and other critical infrastructure. You can scan your domains and subdomains with many tools such as Amass or dirsearch to name a couple.

dirsearch:

Learn more about gau here: https://github.com/lc/gau

I see people use tools like gau and waybackurls when doing recon and analysis before a web app pentest, I am a complete beginner and most tutorials just explain how to install these tools but not why we want to use them or where we want to get using them.

Great :) Would be a great addition to tools like gau or waybackurls for people with an API key!