How about giving us a clue on your growing situation. ? ?
I'm on my 4th decade of growing indoors and out and have never had a problem with bud rot. But I realize it can be a problem where humidities are high.
"How often should I spray my plants with anti fungal insecticides while flowering."
The statement "anti-fungal insecticides" does not make much sense.
There are fungicides, which treat fungus diseases.
And there are insecticides which treat plants for insect problems.
I am sure there is something out there that treats both fungus and insect problems but for sure as fuk you do't have a clue about what you are doing, and are willing to hose your plants with chemicals when you do not understand any of the processes or science behind any of it.
Anti-Fungal Insecticides..... Give me a break....