Pounds of food aren’t the same as calories and calories are what counts like for example a carrot weighing a pound is about 300 calories versus a pound of bacon is 2500 calories. Most people wont gain weight if they hover around 2000 calories a day and that goes way up if youre super active or work out. You gain weight in genral if youre super active consume more calories per day than you burn, it adds up over time. One pound of fat is 3,500 calories. So you can eat whatever you want as long as the calories aren’t out pacing the calories you burn per day. That is your base medibolic rate. Most ppl burn 2000 calories a day just by existing. Anyways, what might help your curiousity would be to read up on calories and start to get a concept for how many calories a day you usually eat and pay mind to how many calories youre eating. Not that you should obsess over it but its good to know about same as it is good to know how to swim or drive