This model has lots of faces htat are hard to see. Is there any way to select all connected faces of a selected face? Ctrl+L doesn't work.
Normally, in edit-mode you can select connected faces via Ctrl+Num +. This is called growing selection and works for vertices and edges as well. With Ctrl+Num - you can shrink your selection accordingly.
Since Ctrl+L does not work, growing selection will not work either, since your faces clearly are not connected. Maybe you ripped them accidentally. Try selecting all vertices, hit M for Merge, and click By Distance. This should meld all faces together again.