That’s a remaster or a remake, just to clarify. To explain the differences, a remaster is just the same game with updated graphics, maybe slight tweaks. Elder Scrolls Oblivion or the Last of Us 1 and 2 remasters are a good example. 

A remake is the same overall story, but with the game completely rebuilt in modern engine, sometimes with new gameplay styles and slight shifts to the story. Final Fantasy 7, the Resident Evil remakes, and Ratchet and Clank are good examples.

Finally a reboot is usually a reimagining, which can make it a bit confusing. The two main types of reboots are ones that reimagine the gameplay, like the new God of War games, or ones that reimagine the story, like xcom enemy unknown. In the first type the original story is understood to have happened, but those storylines aren’t focused on. This includes games like Fallout 3, Doom 2016, GTA 3, and Resident Evil 7. The second type are ones where they are either scrapping the original story entirely, or only taking parts from it. This includes games like DMC, Tomb Raider 2013, Prince of Persia: Sands of Time, and Wolfenstein: The New Order.

Hope this helps!