I always fed my fish twice a day, just what they could eat in a couple of minutes.You do not want to overfeed! Plus they can go without for a day. Just feed him right before you leave...don't put more food in there cause it will just dirty the water.
What you're doing now seems to be okay, but twice a day is better. About 3-4 pellets of food in the morning and at night is best.
if you go away on a trip, then yes, he will be fine while you're gone for a day or two. If you are going to be gone for longer, then you should get these small white slabs of nutrients that dissolve in the water and keep fish alive.
you can feed them up to three times a day im not sure it matters if its at the same time and yeah they can skip a day or two as long as the temp is right
once a day is more than enough, it is recommended 2 or 3 pellets once a day. if you go on a trip they will be absolutely fine. I have two and i live in college and they are back home. i go home twice during the week and the weekends so they only gte few 5 time weekly and they are fine. just make sure to change there water the more you feed them because if you do not the water will cloud and become smelly
Your betta has a stomach the size of his eyeball, and you need to feed accordingly. I like to feed 3-4 pellets a day, usually at once.
In answer to your other question, one day without feeding should be fine. I acutally plan for a fast day each week, a day when my bettas are not fed at all because this gives their GI tracts a day to clear out the residual food and is very cleansing.