Error"model definition can not be found" while simulating design using Google Skywater PDK in SPICE

[farin64]

Hi All,
I was trying to simulate my design in the LTSPICE with the spice directives for PMOS and NMOS models using the file "sky130_fd_pr__nfet_01v8_lvt".
It is giving me the following error that says it can not find the definition of model "sky130_fd_pr__nfet_01v8_lvt_model" L=1 W=1.
Where I have used the length and width of the NMOS as 1 (just for the purpose of testing).
My questions are-
** Why are there 38 models all together in the library file?
** How do I choose which model is appropriate for my design so that it won't generate the error I am currently getting?
** This is how I am calling the model directive-
'Ctrl + right click' on the nmos4. Component Attribute Editor opened I changed the prefix value to X and value to "sky130_fd_pr__nfet_01v8_lvt" which is after the .subckt statement in the model file.
I added the SPICE directive which I have copied from GitHub and named it nmos4.lib as .lib nmos4.lib
** Is the error generating because I am not specifying which model I am choosing out of the 38 models presented in the "sky130_fd_pr__nfet_01v8_lvt" file under the subckt called by the same name?
I would appreciate any kind of help to solve this issue.
TIA!!!!! (edited)

[proppy]

@farin64 can you confirm how/where you installed the PDK and how you're referrencing it from LTSpice?

@mithro should we have a label for tools-AnalogDevices-LTspice?