You can calculate electronic charge density (ρ) and its Laplacian (∇2ρ) in Gaussian using AIM=All keyword. The values are printed in output file but there is no option to see the critical points in Gaussview. If you want to do calculate and visualize the critical points use separate program e.g., AIMALL, Multiwfn etc...

Thank you so much Dr. Debasish Mandal for your attention. 

what are the applications of electronic charge density (ρ) and its Laplacian (∇2ρ) ? and how they can help us to understand more about the interaction process or sensing ability of a sensor or and adsorbent?

Dear Dr Mandal, Would you please give the full keyword that can be used for this calculations?

Please see the output file (attached here) for a sample AIM calculation. For the analysis and significance of AIM theory there are so many web resources e.g., http://www.chemistry.mcmaster.ca/aim/aim_0.html

Dear Dr Mandel,

Many than ks for your kind and helpful reply.

Dear Dr Mandel,

woul dyou please guide me how to find the electronic charge density (ρ) and its Laplacian (∇2ρ)  in this .log file?

See the section "Properties of atoms in molecules using the SCF density."

From the table "II. CRITICAL POINTS ON ATTRACTOR INTERACTION LINES"

you will get the Laplacian and electron density of the bond critical point.

one more point: Gaussian is not so good for AIM calculation. There are a number of free program e.g., XAIM, Multiwfn etc. you can try. The manuals are very easy and straightforward.