So I’m currently a Cobol programmer, been going through FCC and learnt quite a lot, how do I know I’m ready and should I move?
I’m not sure I understand the question. Your title seems to be asking a different question than you text, which is vague.
COBOL? There’s some work for that working on legacy code. But learning some other stuff would be useful. Learning another language would increase your employment possibilities.
The FCC stuff? It is a good start, but there are lot of other branches in web dev to go down. FCC gets you a taste of a complete stack, the MERN stack. Keeping learning that stack and continuing down that path would do you well. And there are many things you can learn to support that.