White patch on teeth is usually an early caries so requesting you to visit dentist and get it checked asap.

Hello, its called white spot lesions, initial phase of dental cavity if it is not treated at this stage it will become a full fledged cavity, this can be reversed by maintaining good oral hygiene, application of fluoride varnish by the dentist, use of demineralizing tooth paste, night time bottle feeding should be avoided, reduced consumption of sweet, should brush twice daily, snacking in between the meals should be avoided.

Hello It may be dental caries,or demineralised part of teeth.consult through this or physically for proper diagnosis and treatment

This is any early start of dental decay