If I eat 2000 calories will I lose any weight?

you should eat more than your BMR and less than your TDEE.

If you are already very lean and just want to lose the last few lb of stubborn fat, then eat 10% less than your TDEE

if you have a significant amount of fat to lose, i.e. you're obese, then 20% less than your TDEE is better

if you are severely obese you can probably eat 25-30% less than your TDEE, but it's generally advised not to eat less than your BMR calories

Think about it this way, your BMR calories is the energy needed to keep your cells alive and your organs functioning right. If you eat more than your BMR but less than your TDEE, you're burning fat through being active, while feeding your body what it needs. If you're eating less than your BMR you're not giving your body enough energy to keep your basic functions going... if you create too big a deficit (i.e. eat too little) you'll be battling hunger all the time, and you have a greater risk of losing lean body mass along with the fat, which results in your metabolism slowing. That's why it's important to lose fat slowly. You lose the weight too quickly and it's pretty much guaranteed that it's not just fat that you'll be losing.

Hey, So my BMR Is 2187 and my TDEE is 3000 something, And I was wondering If its okay to eat 2000 calories?
And If its okay How many pounds will I lose a week?

You'll lose between 1-2 pounds per week, assuming your calculations are correct. Unfortunately you're at risk for losing a lot of muscle along with the fat b/c you're eating under your BMR. That can lead to a decrease in your metabolism that might make future weight maintenance or weight loss more difficult.

If you're relatively new to this, consider shooting for only a 500 calories per day defecit, eating plenty of protein (1 g per lb lean body mass), and doing resistance training.

2200-2500

Do the math. 3500calories = 1lb. If your TDEE truly is 3000 (are you really active? MFP tends to overestimate) then you'd be losing a pound every 3.5 days, or 2lbs every week which is the high end of recommended. Certainly try it and see if you lose, if not, you know your TDEE isn't really that high and you need to lower your calories.

Do you have a citation for this tendency of MFP to overestimate TDEE? Its use of the NEAT method has fairly consistently shown up as lower TDEE numbers than, for example, the calculators at Scooby's Workshop, when I've mucked around with them.

Don't put your weight loss on more then 1lbs.
MFP don't tell U to do so.

Do the math. 3500calories = 1lb. If your TDEE truly is 3000 (are you really active? MFP tends to overestimate) then you'd be losing a pound every 3.5 days, or 2lbs every week which is the high end of recommended. Certainly try it and see if you lose, if not, you know your TDEE isn't really that high and you need to lower your calories.

Do you have a citation for this tendency of MFP to overestimate TDEE? Its use of the NEAT method has fairly consistently shown up as lower TDEE numbers than, for example, the calculators at Scooby's Workshop, when I've mucked around with them.

No need for a citation. My doctor and dietician calculated my BMR to be 800 calories less than the online calculators and my TDEE to be (though it changes daily sometimes drastically) around 1500 on a normal day. MFP had me at 2750

That seems anecdotal, rather than general. In other words, the fact that your doctor indicated MFP's numbers (and - apparently - every other TDEE calculator's numbers) were too high in your specific case is not necessarily indicative that "MFP tends to overestimate."