You're already making a good start by reading labels. Don't sweat it too much; there are a lot of excellent things to eat that will help you lose weight without losing your mind.
If you're counting calories, the thing to look for on the label is just that: calories. (Pay attention to serving sizes, too; companies like to call one muffin two "servings," but c'mon, that's just not honest.) Compare with other foods and you'll see some trends. Higher-calorie foods generally have more grams of fat and/or carbohydrate (including sugar) per serving. They also tend to be more heavily processed foods, so a lot of people have success keeping their calories low just by choosing less processed foods at the grocery store.
Sodium has no effect on fat. It might--key word,
might--be a health concern if you have high blood pressure and are salt-sensitive. It will also make you retain fluids in your body tissues, so eating a lot of it might cause your weight to stall--but remember, that's a weight-loss stall, not a fat-loss stall. Some people avoid sodium, others keep an eye on it, and others ignore it; it's up to you and your doctor which thing you do. But one thing it
won't do is add fat. Don't feel as though you MUST buy low-sodium stuff.
Do you like non-starchy vegetables and fruits at all? I notice that your menu so far doesn't include them. You'll have a much easier time cutting calories if you add plenty of veggies and a fair amount of fruit to your plan. Vegetables pack a very small calorie wallop for their size; you'll feel much fuller if you include at least a serving of vegetables in every meal.
For example, my breakfast today was a two-egg omelet full of spinach, onions, and
salsa fresca that we made ourselves (it was really easy and the link shows the recipe). That omelet and the butter/oil combo I used to cook it plus an orange set me back about 280 calories for breakfast--and it was so filling.
Don't be afraid of food. Your body needs it and your mouth enjoys it. Just select foods that are less calorie-dense or that offer you some kind of health benefit. That egg you had this morning was a good choice, and (surprisingly, maybe?) the hot dog wasn't bad either. But the bagel and the bun added little but quickly-digested filler and calories. They aren't "bad" foods--they're just not doing you any favors. There are other choices that'll keep you fuller longer.
Tomorrow you can try replacing the empty carbs with a bowl of high-fiber cereal, oatmeal, or grits for breakfast. You might prefer to make that egg into an omelet. Or try a version of an egg McMuffin: whole-wheat English muffin, a slice of cheese, an egg, and a slice of tomato comes in at around 300 calories (less if you use low-cal cheese, but I love my real cheese). For that hot dog, try it with a whole-wheat bun with onions and peppers or relish as a topping. Or skip the dog and go with a sandwich wrap stuffed with your favorite lean meat(s) and plenty of greenery.
Don't let labels mystify you. It soon becomes second nature to check them. This stuff actually becomes fun once you do it for a while.
Scared To Eat
However, I'm still oblivious to the eating right part. I want/need to lose 100 lbs but I know I won't get there if I'm still eating the foods that got me here in the first place. 
