Please note that we do not provide a recovery alongside CalyxOS. You can try to use a recovery of your choice, we will not make a recommendation. However, if installation fails, we will not help you. You are entirely on your own.
Download the build using the drop-down menu above, sideload it, format data and you're ready to go. For detailed instructions, e.g. regarding unlocking the bootloader, please read our LineageOS wiki.