By installing Microsoft Office on your Mac running OS X Lion 10.7.5, you'll enjoy numerous benefits, including:

Modern software relies on 64-bit optimizations and instructions missing from older Intel Core Solo or Core Duo processors found in early Lion-compatible Macs.

For unsupported hardware, community-developed patcher tools (like those by dosdude1) can force-install newer macOS versions, thereby unlocking compatibility with newer Office versions.