The best way to correct crossed eyes, which is clinically known as internal strabismus, is through surgical treatment. The first step is to go to the hospital for a professional examination to check what type of internal strabismus is, whether it is accompanied by other types of strabismus, strabismus-related tests, etc. The next step is for the doctor to perform the surgery, which is usually performed under local anesthesia, unless it is a special type of strabismus, and the results are clear and reliable. It is recommended to find a professional doctor for surgery after examination. I hope this can help you.