Car heater stopped working months ago, but now that it’s getting colder, I decided to try and look for a fix to this issue.

I’d like to start off by saying I know damn near nothing about cars 😅

So, I opened the fuse box and the the HVAC Fan fuse was completely melted. I was able to pull out the fuse, but the inner casing that the fuse connects to also got melted.

Is there a DIY solution to fixing this fuse box, or will I need to buy a replacement (around $50 on EBay) and pay a mechanic to change it? And if that’s the case, what would be a rough estimate of the cost for the job?