There is a chance you are viewing your project in "Solid" viewport shading. Press Z, it should show you 4 options: Wireframe, Solid, Material Preview and Rendered. Choose on of those last options.
I'm betting that is it, so if you still don't see any improvements let us know, and make sure you attach your model and texture files, so we can make sure if there is something else needed to be done.
I'm betting that is it, so if you still don't see any improvements let us know, and make sure you attach your model and texture files, so we can make sure if there is something else needed to be done.