I wasn't able to locate a BIOS version on the box, but it did state it was version 1.2 of the motherboard itself, and it is labeled as Ryzen 5000 ready. Does that help at all?
Unfortunately, "Ryzen 5000 series support" can mean multiple things. The Ryzen 5 4500 is supported by the motherboard with the right firmware, but this processor was actually released after AMD's full lineup of 5000 series CPUs. The webpage for the motherboard states that the BIOS version for the 5600X is F10, thus making it "Ryzen 5000 ready," but the 4500 is supported via the later F14 revision.
Fortunately for you, this motherboard offers Q-Flash Plus, which means it is able to flash the BIOS without a compatible CPU (you can even remove the CPU and ram, all you need is power for the BIOS flash). Read your manual for how to use Q-Flash Plus on this motherboard, and also look at a YouTube tutorial. Follow the instructions carefully and you should be able to update the motherboard as needed.