I have woozy feeling,brain fog and eyesight problems from 2 years now,i have had every test possible which are clear except low vitamin b12(227pg/ml).

Testing?: I know you said you have had every test but just to confirm - you should have a comprehensive dilated eye exam, MRI of the brain, glucose testing with glucose tolerance test, and a methyl malonic acid lab test which helps to clarify the B12 deficiency, as well as other CBC and consider heavy metal exposure screening. You should be getting B12 injections before you go on oral supplementation.