Do you have trouble running this game on Windows? Read this guide.
DOS games can't run on Windows. You need a DOS emulator like DOSbox or D-Fend Reloaded. Follow these instructions to play DOS games on Windows 10 or later systems.
"L'Eternauta is a popular south american sci-fi comic book. It's not as popular as Marvel or DC comics, but some (many?) people may know it. L'eternauta was published in Italy and distributed in newsstands as a series of videogames. Unfortunately, it's awful and uninteresting. There's little logic in the aimless wandering around Rome looking for new locations and NPCs. L'Eternauta could have been a better game: a wasted comic license." - Abandonware DOS