I have a doute with spirit resolution

I making a 2d assets for my game but I want to know in which resolution that the spirit will export for hd game. Isn't I export the spirit in 720p or 480p or lower? 

It looks like you are having trouble translating.  I'm guessing you mean "sprite" instead of spirit.  As far as what resolution to make your sprites, it depends on the game, what devices the game is for, how you are making them, and what you know how to do.

Some games are made lower resolution on purpose, and it doesn't matter what device they are on.  The pixelly look is the art style for those games.  You mention "hd game" so I'm guessing you may not want pixel art but higher resolution art instead.

If the game is for PC, you can do anything from low resolution pixel art to anything modern PCs can do.  If the game is for mobile devices, you may not want as big of a resolution, so you wouldn't want as big of sprites.

Before you can really know how big to make the sprites, you need to know what actual screen resolution you are targeting.  Then, you would make your sprites the appropriate size for your game at that resolution.  Some games need small sprites but show a lot of the world around you.  Some games show the player much bigger, but show less of the world around them.  These are decisions you make before you start drawing your sprites.