Navigate to a web-based tool like [Cubical.xyz]. Upload: Drag your file directly into the browser viewport.
If you want to view a blueprint while physically building it in your world, mods are the absolute best choice. Minecraft Schematic Viewer
: A newer, free 3D viewer designed specifically for .litematic and .schem files for players who get lost following traditional video tutorials. Mobile and Specialty Options Navigate to a web-based tool like [Cubical