Cats are animals of habit. For them it is very important to have a routine, and that it is changed as little as possible and, in the event that it has to be done, either because the family is moving or because a new member is going to join the household, it should be done gradually so you have time to get used to it.
With the eating schedule you also have to be cautious: you must set a schedule and follow it. But of course, when doing so, one of the questions we ask ourselves the most, especially if it is the first time we live with a feline is: How many times do you have to eat?
The answer is not always easy. There are cats that eat twice a day, others eat the feed throughout the day, and there are others who eat at specific times of the day. My advice is that, at least for a day (or whatever you need) leave the feeder with his food at his free disposal, so you can write down what hours or less you are hungry
If you work all day, it is best if you let him eat when he wants. Cats generally know how much to eat. Y they do it so well that they stay within a suitable weight. Look on the bag of feed for the recommended amount for your weight and age to know the grams you should eat per day, so you will not have to worry about becoming overweight.
In the event that he is neutered / spayed, if your vet says he is an ideal weight, don't worry about the quantity. If you stay active and healthy, you do not need to lower the grams nor that you buy him a special feed.
Continue giving him the same amount that you gave him until now, and you'll see how he maintains an enviable state of health.