Hi I ve just written by myself. Pls correct for me
AFTER I LEFT UNIVERSITY IN 2017 BECAUSE I DON'T LIKE MY MAYOR IN CHEMICAL ENGERNEERING. I DECIDIED TO TAKE GAP YEAR TO FIND OUT WHAT MAYOR I LIKE. IN MARCH 2019 I TOOK A ENGLISH CLASS TILL NOW TO IMPROVE MY ENGLISH SKILL AND SUPPORT FOR MY FUTURE CAREER SO I STILL HAVEN'T APPLIED FOR ANY JOB YET

Question

Hi I ve just written by myself. Pls correct for me
AFTER I LEFT UNIVERSITY IN 2017 BECAUSE I DON'T LIKE MY  MAYOR IN CHEMICAL ENGERNEERING. I DECIDIED TO TAKE GAP YEAR TO FIND OUT WHAT MAYOR I LIKE. IN MARCH 2019 I TOOK A ENGLISH CLASS  TILL NOW TO IMPROVE MY ENGLISH SKILL AND SUPPORT FOR MY FUTURE CAREER SO I STILL HAVEN'T APPLIED FOR ANY JOB YET

Answer

An excellent effort using some complex and compound sentences! 
Here are a few more suggestions.

In 2017, when I left university because I didn't like majoring in chemical engineering, I decided to take a gap year to discover which major I preferred. Since March 2019, I have been taking English classes to improve my English skills and support my future career in which I have not yet found employment.

Hope this helps

Answer

AFTER I LEFT UNIVERSITY IN 2017 BECAUSE I DON'T LIKE MY MAYOR IN CHEMICAL ENGERNEERING. I DECIDIED TO TAKE GAP YEAR TO FIND OUT WHAT MAYOR I LIKE. IN MARCH 2019 I TOOK A ENGLISH CLASS TILL NOW TO IMPROVE MY ENGLISH SKILL AND SUPPORT FOR MY FUTURE CAREER SO I STILL HAVEN'T APPLIED FOR ANY JOB YET

Corrected version:
After I left university in 2017 because I DIDN'T like my MAJOR in chemical engineering, I decided to take A gap year to find out what MAJOR I like. In March 2019, I took AN English class UNTIL now to improve my English skill and SUPPORT MY future career so I still haven't applied for A job yet.

Answer

Can I write it in any better way?

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