I have been trying to import an entire level from unreal to unity but however it looses all its textures during the process. Please help

what format? I find when I import an fbx into unity it NEVER comes in with textures. The shaders are all there but the texture field is empty. I need to import the textures separately, then drag and drop them into the texture slot of the shader in the inspector window

You can try using my tool : https://assetstore.unity.com/packages/tools/integration/exporter-for-unreal-to-unity-193237 It exports materials and textures accurately.