Hello sir
Definitely the squint can be corrected by surgery.
More importantly we need to understand whether the decreased vision is because of Amblyopia or cataract or any retina issue. The success of squint surgery and the life long maintenance of proper eye alignment will depend upon the cause, whether it is sensory, stimulus deprivation or nerve related
Next Steps
Better to get a physical consultation with Strabismologist and Neurophthalmologist