No, Rick and Morty is not a remake of Back to the Future. While the two properties share some similar elements - most notably, time travel - they are otherwise quite different.
Rick and Morty follows the exploits of its titular characters - an eccentric scientist named Rick and his nervous grandson Morty - as they go on wacky adventures through time and space. Back to the Future, on the other hand, is a more family-friendly adventure that sees protagonist Marty McFly accidentally traveling back in time and having to ensure his parents fall in love or he'll cease to exist.
While both properties are enjoyable in their own right, it's clear that they are very different stories. So no, Rick and Morty is not a remake of Back to the Future.