You just need a cable that ends up with USB-A instead of -C. You don’t need a USB-C Mac to use USB-C peripherals. What you need is USB3 and your Mac has that via USB-A ports. Fortunately, plenty of enclosures come like that.
https://www.amazon.com/dp/B07D2BHVBD
https://www.amazon.com/gp/product/B07Q9YDX5Q
And of course you could even get one that comes with a cable with twin USB-C plugs and then just swap the cable or use a USB-C to USB-A adapter.
https://www.amazon.com/AmazonBasics-Type-C-Adapter-Charger-Cable/dp/B01GGKYR2O/
https://www.amazon.com/gp/product/B07B47V967
The Samsung 870 QVO 1TB by the way just today went on sale for $90. That’s the lowest price it’s ever been by quite a margin. I had to order one. ;)