Ok here comes a Newbie question

Not dumb at all. But always look for the entries that are for the raw meat and use that as your guide for measuring.

When you cook meat it only loses water and some natural juices, but it can lose different amounts based on the meat and how long you cook it.

So if you have a 4oz piece of raw, boneless, skinless chicken breast, it will be 120 calories.
A. Cook it to perfection, so it's still moist and juicy inside, and it will probably weight around 3.5oz when it's cooked.
B. Overcook it so it's dry and probably a bit tough now, it will weigh closer to 3oz.

For both option A and option B, you still have 120 calories of meat. But if you'd weighed it after you'd cooked it, you'd be logging 105 calories for A and only 90 calories for B.

Always weigh everything, not just meat, prior to cooking. Meat for the above, and stuff like pasta, rice, and beans should be weighed before because they will increase in weight, so you'd be shortchanging yourself on what you get to eat. For example, 43 g of uncooked rice turns into around 150 when cooked (though has a range of 140-160 depending on how much water it absorbs), so you'd be getting only a third of what a serving size would be if you weighed out 43 g of cooked rice for yourself.

Unfortunately due to density, there isn't any way to have an easy conversion from cups to grams. Like, a liquid cup of honey will weigh more than a cup of water or a dry cup of rice will weigh more than a dry cup of marshmallows.

Instead of always going off of the database here, I often use nutritiondata.self for fruits, veggies, and some meats. They have the option to select the food item by 100 g and it will give you all the nutrition info for that amount (the potassium level is listed below, in the minerals section, not in the main "label" section at the top) whereas a lot of the entries for fruits and veggies in the database are listed by the cup, which isn't as accurate anyway. I've actually entered pretty much all of the fruits and veggies that I eat into My Foods using that database and the 100 g option.

The general rule is anything that is liquid, use a liquid measure in whatever measurements are on the food label you have on the item in front of you. And for anything non-liquid, use the weight option. Always opt for what the label says over what the database says (I say this because I'd suspect that in the UK it will use measuring options you'll be more familiar with).

And if the label gives an option like "1/2 cup (43 g)" always use the 43 g because it will be more accurate anyway (again, that is for dry measure stuff, liquid items will still need to be done by liquid measure).

I had the same problem, but if you go into poundland you can buy sets of cup measurements, I bought ones from 1/3rd of a cup upwards as my sister and I often swop recipes and weight loss tips as she is married to an American and I couldn't do her recipes without them, plus it means I can do recipes and convert easier for her.

When weighing out food are the Nurtional Info for uncooked/raw weight?

God i sound dumb,,,lol

Not at all dumb, good question. In short, no they're not, unless the label reads 'RAW'

For generic foodstuffs like meat and veges, I always search for 'GENERIC' + 'RAW' + [food name]

ie GENERIC RAW BROCCOLI or GENERIC RAW CHICKEN BREAST

Where it's already been cooked - we occasionally get a roast chicken from the supermarket - then stick with the cooking method and description, ie ROAST CHICKEN BREAST MEAT

Try to weigh before you cook, always note your sauces etc as well as they have an effect on sugar / salt / carbo intake too.