Statement:
The level of criminal activities is lower in Nepal than in Afghanistan

In the The Most Criminal Countries rating Nepal holds position #94 ²⁰²² out of 139 and Afghanistan is #3 out of 139 ²⁰²².
Position of Nepal is better than position of Afghanistan.
Afghanistan is leader of the "The Most Criminal Countries" rating. So it is wise to avoid visiting the country or, at least, you need to take additional actions to protect your life and belongings, compared to Nepal

Referencies:

1. The Most Criminal Countries ²⁰²² by Numbeo

   The countries in the rating sorted by 'Crime Index' in descending order.

   Afghanistan	'Crime Index' value is	78.19
   Nepal	'Crime Index' value is	37.77