Losing weight isn't that complicated...
Your body requires a certain amount of calories to maintain it's current
weight (body weight in lbs x 15)...so if you were 150 pounds, that would be
150x15 = 2,250 calories/day.
To lose 1 pound you need to be in a deficit of 3,500 calories. So if
you ate 500 calories less than this 2,250 each day (1,750 cals/day) you would
lose 1 pound each week.
Couple that with 1 hour of cardio each day (500 calories burned/h on
average)..you'll burn another 1 pound a week.
Other than that, the only other suggestion I would have is to make it a habit to fill yourself up on vegetables and salads as they are low in calories and will make diet adherence easier.
Also, cut out most processed foods and stick to veggies/lean meats + a few fruits/nuts.
Soups, although processed, can also be a good way to stick to a diet as the combination of solid+liquid in this way tends to do a good job of filling you up, keeping hunger at bay.
Coffee of course would help too as an appetite suppresant.
If you need to learn more, this will explain things in detail..
Use this Calorie Calculator (Click Here) to give you a "Rough" idea of how many calories you burn up per week and how many calories you need to take in to create a Deficit of Calories which will result in you losing weight.
Here was my results:
I put in "Moderate Activity" but when I work out I grind the calories right up. I do "Dead Lifts" once a week and "Heavy Squats" once a week which peak my metabolic rate, and decimate the caloric intake for that day.
The key here, is to take in less calories then your body needs to burn. Your body will seek other way to burn energy in the way of "Stored Energy" (fat). You want to force you body to use up those reserves. Start by altering your diet . . . Absolutely NO sugary soft drinks. Also, no DIET soft drinks because this messes with the brain and can increase insulin manufacturing.
Do water and unsweetened Iced tea (like Pure Leaf Unsweetened Black or Green tea). Occasional fruit juice but rarely . . . If you have issues with just water, I suggest water with fresh lemon squeezed in it. No more processed foods . . . No more McDonald's, Wendy's, . . . Etc. (Use this as a treat every 3 months if you must). Go to a plant based, lower dairy, and lower meat intake diet. Increase your protein depending on what you end up doing for work outs.
If you create that deficit, your body will start using the stored energy (fat) . . . Any increase to exercise will result in your body using MORE of the stored energy (Fat), and quicker results.
Don't be discouraged . . . It didn't take you over night to gain the weight, so it will not take overnight to lose it.
When it really comes down to it, the only way to gain weight is to take in more calories than you burn off. Gaining weight can most effectively be done through a regimen of (healthy) food eaten in proportion combined with consistent weight-training exercise. Truth be told, you burn off a majority of your body's daily calorie usage simply by being alive, breathing and maintaining body temperature, etc. The swimming won't help you gain weight either (I used to swim competitively for years), as it burns off an absurd amount of calories.
The amount of calories your body uses in a normal day is called your maintenance level. If you consume this many calories and do not exercise, then your weight will stay the same. What you want to do is get your calorie intake to be ABOVE-maintenance level, where you take in more calories than you burn. This is the only way to gain weight (naturally). There are online calculators to roughly determine your body's maintenance level given your body and your level of physical activity. I recmonded you Macro calculator app through this you get more results about Macro calculator .