You can find the guidance on Comprehensive Food Security and Vulnerability analysis  (CFSVA) 

https://www.wfp.org/publications/comprehensive-food-security-and-vulnerability-analysis-cfsva-guidelines-first-edition 

For the most updated dalaysis scripts of Food security indicators you can visit (WFP VAM resource centre) 

https://resources.vam.wfp.org/ 

Here is the guidance to the consolidated approach for reporting of food security indicators (CARI)

https://resources.vam.wfp.org/data-analysis/quantitative/food-security/technical-guidance-for-the-consolidated-approach-for-reporting-indicators-of-food-security-cari