There is no need to use floats for this layout.
Start with a div block, 100% width. Make it flexbox and set its direction to horizontal.
Inside this div block, place 2 more div blocks. Inside one of the div blocks, place your brand and the 3 page links. Then in the other div block, place your ‘Sign In’ link and ‘Request Demo’ button.
Then, you have two options for making these 2 children div blocks ‘push’ to either side of the parent div block…
You can either do it using the
justify-content: space-between property on the parent div block, like I mentioned earlier.
Or, you can select the child div block which is housing your ‘Sign In’ link and ‘Request Demo’ button and give it a left margin of
auto to push it to the right-hand side of the parent div (see the tutorial I linked to earlier by Mackenzie, as this is the method he walks through in the tutorial).
Unfortunately, I don’t have any project space left in my account, so I can’t make a demo for you. Do you have a read-only link to a project you have started? I could make it for you there and screenshot the layout structure for you.