But since now my English is still not good enough. I also want to learn more. I probably will get knowledge and especially useful if you advise and correct errors in my English writing.
But now, because my English is not good enough. I still have to learn a lot more. I would have been knowledgeable and helpful if you recommend and fix mistakes in my English.
But because my English is not good enough now, I still have much to learn. I'll get the knowledge and especially useful if you introduce and correction of errors in writing English.