Trending @HCL; HCL is working in hybrid model or 5 days WFO ... If it is hybrid how many days WFO is required?

Depends on project to project.
One observation: Whichever project has multi location team members and whichever team has more women folks, then that project is most likely going to be a work from Home project.

3 days a week or 12 days in a month

I'm still doing WFH. Depends on the project I guess.

If you are in a project, then depending on the project requirement it may take 5 days or 3 days in a week. If you are on the bench then you need to visit the office for 5 days. My project is the worst project which I have ever seen, they are asking to work weekends and take rest on weekdays. F hell it is.

There must have three days off and rest day office

3 days a week