Due to smoking only the patches, which are non scrapable, has appeared.
QUIT any kind of tobacco Smoking/chewing IMMEDIATELY.
Maintain oral hygiene by brushing twice a day, after food intake.
mouthwash once in every 2 days, after food
Tongue cleaning regularly.
Have TOMATO as much as possible. make sure
uric acid within normal limits.
The patch will not disappear but won't increase either, shall remain asymptomatic.
Next Steps
visit dentist to elicit if any other patches present in your mouth, lasers can help and remove the white patch if you feel its presence very bothersome esthetically.