I don't know any other way than to enter the schematic in KiCAD from scratch. (LT)Spice misses a lot of information that is required to layout a PCB, e.g. pinout, case types and sizes etc., therefore an import from (LT)Spice to KiCAD would require a lot of manual re-work. It is faster and less prone to error when you enter the schematic in KiCAD anew.