Hi sir am having some kinda patch inside my mouth on right side. Is this a serious problem cause am worried bout it please let me know. I smoke cgrtte?

Smoking. The "patch" would have to be personally examined by your own dentist, preferably an Oral Surgeon for a clinical diagnosis. Any type of tobacco increases your risk of cancer, regardless! It's your health and your life, and you must take responsibility for your actions.
More info needed... This patch... how long do you have it? Does it rub off? White or red in color? As you can see, this needs to be Physically evaluated. Please see a local dentist.
Patch. I'm sorry, "some kind of patch" is not a sufficient description. To be properly diagnosed you will have to see a Dentist or Oral Surgeon. The fact that you smoke puts you at risk for oral cancer. Please seek care immediately.
Smokers' Keratosis. White patches on the palate, tongue or the inside of the cheeks can be caused by smoking. In many cases the patches may disappear if you give up smoking. It is essential to see you dentist immediately so you can have peace of mind.
Examination. Need more info and examination to know more. If it is white and remains after you reach in and stretch your cheek, then it is of concern. See the Oral Surgeon to evaluate this. As a smoker you are at a much greater risk of oral cancer. Make the appt. Good Luck.