[aidos]

You've been given a lot of good advice on here - I concur with all of it. After almost 20 years of writing code I still couldn't tell you how long it would take to debug something in my own codebase. If I can visualise it, sure, I can take a guess, but if not, who knows what I'm going to find.

Given the questions you've asked on here, it really sounds like you were just in a bad environment. You said 3 hours, it took a week - you're a junior, why the hell didn't someone jump in to help out?

Everything you've asked comes down to experience and you need people around to support you in gaining that experience.

Good luck finding a nicer workplace - honestly, sounds like you have the makings of a good inquisitive developer mind. There are plenty of places out there that will help you develop your full potential.