Essays / Need topic to practice, writing an essay for the first time [4]

I felt bad today upon receiving my report card. I got 5 band score on my essay writing. I need to get not below 7.5 over all band score on ielts exam. Can somebody help me improve my writing skills? I need help. Can somebody give me any topic that i can practice writing an essay? I am having a hard time describing and interpreting a graph. I will appreciate it if i will get a reply to anyone of you out there. Thank you in advance. God bless!