seo and many google update

i start working in small company as a employess and try to learn seo from there. after 2 years of learning and make many experience in seo now i start my own company and try to reach my ways to succed from seo. But as the result is always stuck this couple month, i have confidence in my site because already rank in few good keyword last month but after google update my site last night i have lost in many keyword !! must i quit from what i do now ?

don't quit mate. it is just as it. you'll never get to the top if you stop now. Go for it! Chase your dream!

Keep working let the ball come in your court

it really hard for me dude and im still working on it. i just nearly get ranked in first page this month and all be gone this few days.

Losing ranking/traffic within updates is a thing that you should live with if you're into SEO,
It could be caused because of some problems in your website or links built or it could be completely random (even when everything is good to go),
Just focus to keep your websites on-page at its best (technical stuff and content), aim for some good keywords that would make you a good ROI and invest in high-quality links
With the right keywords, even if you get a partial traffic drop, you should keep making a good ROI

Men, only losers stops, the winners newer stop. And also 2 years are not enough for to become SEO expert, you have to learn a lot more