Sunday: coffee Monday: coffee Tuesday: snack and dinner Wednesday: coffee Thursday: snack and dinner Friday: three full meals Saturday: three full meals
Are you able to focus by Tuesday? I feel like I would struggle to be productive.
So skipping breakfast is super easy (IMHO) and skipping dinner is nigh impossible.
Skipping lunch highly depends on how pressured you feel to eat with your colleagues. I think one meal a day (usually named OMAD) is also not hard if you don't have lunch at work.
I'm able to focus any day. Some months I do 1 week when I fast Monday, Tuesday and I eat dinner on Wednesday; body reboot.
I began to fast gradually and this is what I consider my optimal IF method.