If you already have .chk file corresponding to optimized geometry, just use guess=read to use wavefunction in the .chk file as initial guess, and meantime use pop=npa to obtain NPA charges. The task should be completed very soon.

Hello Professor Tian
is Multiwfn able to calculate or extract "natural population analysis" from the .chk or fchk file?
i restarted an opt +Freq job with the keywords opt=restart, pop=nboread... but the output file do not contain any NBO section as it should ( i need the natural population analysis) ! i want to avoid re run the optimization process for time saving purposes