My sudo apt install command is weird after following some instruction

I'm using WSL and I want to download libpng. And so, initially I typed:

sudo apt -y install libpng-dev

and it worked until it returned cannot access archive.ubuntu or something like that (I don't remember the exact output since it happened like a couple of hours ago)

So, naturally, I went to google to see how to fix this. I stumbled upon a question that asked relatively similar things to what I'm experiencing. So I just followed the most upvoted answer (Again, I can't recall which question was that or what the most upvoted answer was).

And the next thing I know, whenever I runsudo apt ...I get a return like this

Reading package lists... DoneBuilding dependency tree... DoneReading state information... DoneE: Unable to locate package libpng-dev

which is entirely different than what I used to had initially. How do I fix this??

Bonus question: How do I install libpng after that? I need to use

#include <png.h> 

on C