You need to recreate the material in Unity. Just import the textures and the model into Unity, then right-click in the file browser and select "New Material". Select this material in the inspector. The default shader should be fine, but if it's not just select the standard lit shader. From here you can assign each texture type (Albedo/base, Roughness, normal, etc.) to their respective fields. With this material created, you now need to drag your model into the scene view so it is added as a GameObject. You can now drag the material you created onto it. After this, save the object as a prefab so you can use it throughout your game.