Dear aspirant hope you are doing well. Yes you can definitely do good score in neet ug exam without coching.If you consistent do your work. There is a will there is way. Self study is also sufficient for every exam, If you study properly in manner way. Yes you can take help of YouTube video for your dought only. Do Not depend on videos . There are no of example who clear neet ug exam without coaching.

Syllabus for neet ug is given in article. You can check out the link

https://medicine.careers360.com/articles/neet-syllabus

Thank you