I think when I self-taught how to read public corporation financials, I did it just by looking up various definitions over time. There are not very many that matter. I did that when I was quite young, so I'm confident most any adult with even very basic financial literacy can do it in an hour to get started.
So for example, Uber, on Yahoo Finance (fairly simple data presentation):
https://finance.yahoo.com/quote/UBER/financials?p=UBER
Columns displaying full fiscal years (you can change that to quarters optionally). And rows showing specific financial information, such as "total revenue" or "gross profit."
There are ~22 rows in a column year in the Yahoo data sets, each displaying different financial data. Of those, maybe a dozen are particularly important for an amateur to know.
So you'd look up the definitions for eg: revenue (sales), cost of revenue, gross profit, operating expenses, SG&A (selling, general and administrative expenses), operating income, income before tax, income tax expense, interest expense, net income. Another that can be useful as a new or amateur investor, is EPS, or earnings per share.
Investopedia is a reasonable option for learning the definitions, although there are numerous sites that will work fine.
Shouldn't take more than an hour to look those up and learn them at a basic level. After a bit of practice, you can scan a multi-year profit & loss (P&L) statement in a minute and have a great idea of how a company is fairing.
A balance sheet can be more complex, although it can similarly be boiled down to a dozen or so things that by far matter the most. You can get the definitions for those things and learn them in under an hour, then practice reading balance sheets.
Then last but not least for an amateur interested in such, would be to acquire practice at scanning through annual and quarterly reports filed by companies with the SEC. They're often obnoxiously long and overflowing with low-value bullshit, however only a small amount of the content tends to matter. I think the best way to keep that under an hour, would be to have someone mark off the segments worth always looking for / looking at in the filings, such that you can learn to jump to those sections to pick out important information. Beyond that, getting good at digesting company SEC filings will take a lot longer than an hour.
I wouldn't attempt to take on all of these things in under an hour, it'd be unreasonable. An hour each to get started however is doable. Starting with the P&L statement.