If I download the newest version, will I lose all of my work from the current version of Blender I’m working with?
Yes, and also your computer and your wallet 
No, sandman2, you won’t. Newer Blender version opens older files just fine. There may be some issues if you try to open files from very old versions (like 2.49), but that’s about it.
Thank You! Preparing to download in 3…2…1