Am I screwed?

Just started my PC build and I wasn't sure in what slots I should but two DDR4 Ram into. So I checked the manual and I noticed it kept showing maximum MHz for ram but I could find 3000 MHz anywhere. Do I have to buy lower ram? I'm sorry if this is a stupid question it's my first time building. Here's a picture of what I mean https://imgur.com/a/Q848Q I have the ASrock X370 Taichi