How do I make .uasset files appear in my content browser

recently a friend has sent a 4k texture pack to me to use in a project. However, when it comes to importing the asset I have no idea why it won’t work. I’ve spent the entire weekend copying it into my content folder then restarting but after all efforts and research nothing works. Is it because of the version of .uasset files clashing with my version of UE4? How can I tell? help is much appreciated.