[urgent][important] how yoga helps me to cure my diseases ?

hey! 15 year old boy here.personally, i believe nature has solution of all our problems and for curing and fighting diseases nature give us ayurveda and yoga

i don't have very big but small problems which disturbing my daily life so pls suggest me how can i cure it.

1. sinus one of biggest problem of my life i explained it here and for this solution i start drinking warm water, start taking steam and now the think which i lack is yoga pls suggest me some yoga asanas and solution which help me to get fit.

2. i am a 180 cm (6 ft) tall guy and very much slim and because of my bad sitting posture or may be because of something else my spine is now slightly tilted left doctor figure it out in ex-ray and because of it my lower back always give me alot of pain in back in this young age. how can i fix my posture and back bone and back pain with help of yoga ?

3. i have glass of 1.5 in my both eyes how can i fix my eight sight with eye yoga ?

pls suggest me solution of this three