Can't get shadows working at all

I have this scene and I’m trying to make it look as good as possible, but can’t get shadows working at all for the life of me. Have tried all the different kinds of lights and the only one that casts shadows at all seems to be the PointLight, but it doesn’t fit what I want in other ways. Can anybody help me figure out how to get shadows working with the DirectionalLight?

Also, unrelated, if anybody has any tips or ideas of how I can improve the graphics in my scene to get it to look awesome that’d be great

maybe your mesh is out of the shadow cameras frustum.

you could have a look here: Weird shadows on collada model

I worked out how to increase the shadow camera’s “frustrum”: Map Preview - CodeSandbox

but now the whole thing is just darker, still no shadows