I just googled "What causes AFib?" and here was a list.
High blood pressure, Hyperthyroidism, Coronary disease, Heart valve disease, Sleep apnea, Heart failure, Obesity, Alcohol, Diabetes, Chronic Obstructive Pulmonary Disease
Stress, Age, Chronic kidney disease, Excessive exercise, Smoking, Surgery, Heavy alcohol intake, Medicine, caffeine, tobacco, or alcohol, Pericarditis, Sick sinus syndrome, Family history, Heart attack, Viral infections
I look at the list and see if anything pertains to me. I do not have high blood pressure, but if I did I would google "How to lower blood pressure" Mine is very low but due to my diet. But if it was high, google what diet to be on to lower it. If you cut out the garbage foods, cut out or way down animal products like dairy, meat, etc, it will come down and do some walking each day. But google and read on many sites, and start doing all you can. Habits usually don't change overnight, but work on it. I have sleep apnea but alleviate it by being angled up with 2 pillows. It works as good as CPAP machine which my sister had and hated it. It mentions caffeine. I eliminate all. Listed is hyperthyroidism. Mine is according to blood test which I get on my own with no doctor. Google that problem on what you can do naturally to help heal your thyroid. I know that eliminating sugar really helps in time. Etc. Read read read.