Publicly traded companies almost always have an "investor relations" page where they give updates, link to annual reports, and house other information meant for their shareholders. Locate an investor relations page by Googling the company name AND "investor relations," or use a Google site search: investor relations site:walmart.com. You may have to click on sub-pages (look for anything that says "Financials," "Presentations," or "Updates") to find exactly what you need.
Here are some examples of company investor relations pages:
Transcripts of quarterly earnings calls, if they happen, are made available via investor relations pages or on the web. They can be a valuable source of both current and past financial information about a company. Try Googling a specific quarter, year, and company to see their call transcript; for example, "walmart q2 2022 earnings call transcript" You can also utilize Google's site search: "q2 2022 earnings transcript site:walmart.com."
Here are a few articles that cover what kind of information you can find out by listening to or reading an earnings call: