The UEFI specification is not the problem for Linux. The problem is Microsoft's other requirement for any Windows certified client: the system must support Secure Booting. This hardened boot means that 'all firmware and software in the boot process must be signed by a trusted Certificate Authority."
Ubuntu 18.04 LTS will be supported for 5 years until April 2023.
Clean install starting with 18.04.2 hasn't been a problem for me.
Download the latest LTS version of Ubuntu, for desktop PCs and laptops. LTS stands for long-term support — which means five years, until April 2023, of free security and maintenance updates, guaranteed.