Not all models offer both options, but the entry level especially has DDR4 variants, while the high end kind of assumes DDR5 is mandatory if you're spending insane money on a mobo anyway.
You can't get both on the same motherboard though, and even if one were made you could only use one of the two types at a time. They were rare but there were boards that supported both in the DDR3/4 change over, but IIRC they were Biostar and pretty crap
didn't think Z690 motherboards could be ddr4 i thought they were all ddr5. guess i've just assumed wrong.