Rather than approaching this theme with the standard "songs with million" in the lyrics/title, I decided to educate myself just a little.
Question 1: what is the certification level given to records that sell 1 million or more? The answer is a little more complicated than I was aware of. If you know the answer to this question, more power to you. Fact is, there are different requirements for singles and albums. As a music aficionado, you likely know that <Certified Gold> requires 500K in sales, and this is true for both singles and albums (but $1 million in sales at the Manufacturer's Suggested Retail Price). Howsomever, <Certified Platinum> places a 1 million threshold for singles and a 2 million bottom line for albums (again, with a minimum total income based on the MSRP).
Diamond status takes the stakes up to 10 million, and then gets even more complicated when we get into Digital Downloads.
Question 2: the first <Gold> record? The first "gold" label was awarded to Glen Miller's <Chattanooga Choo Choo> back in 1942 (probably rightly so) - but it was an "in-house" award that was only later adopted across the board by other labels. My understanding is that the RIAA only came into being after this point in time. You could check out the RIAA website, but I'm not so sure I would rely on their info based on their past public performance.
But - being the powerhouse that they are, we need to pay some attention to the RIAA, and after they got on board, they awarded Perry Como and Elvis Presley some of their first "golds".
I'll go back on my word just a little by relying on the RIAA website: they say that the very first Platinum record was Johnnie Taylor's <Disco Lady>. I confess the name meant nothing to me, but adding in my experience of where music was at at that time - highly plausibly "gold".
And from there ... the rest is probably what you are already aware of .. The Eagles, Michael Jackson, Pink Floyd .... [I couldn't possibly list them all]