I was thinking about this for some days now. Do I still need more curses do be a developer? Or can i start my work just by completing this curse?
There are many threads on this and related subjects, so definitely search the forums: there is lots of great advice.
If you mean going from zero to job-ready, doing all of the certifications will give you a grounding in various technologies that relate to web development, but I would temper your expectations a little.
You are unlikely to be able gain the requisite depth of knowledge just from FCC, you will need to do a lot of research and practice in addition to the curriculum. It’s an enormous subject, so FCC, despite covering a huge number of different things in the curriculum, can only really teach you the basics. It is the same with most courses, officially certified or not: you would be expected to do your own research and learning in top of what is taught, you can’t really expect to just sit in the lessons then walk into a job.