So there are many things i've found on google results that seem like they could be great for my sims, for example a scarf, but sometimes, they lead to sims3updates.net. Said website says "Could not connect u" whenever i try to enter it . Where do i find the downloads that were on here? And if anyone knows why the site does this, please tell me!

Sims3updates is a cc finds site, just like your regular cc blogs on tumblr. It's probably a dead site now, since it hasn't updated since 2016. What I would do if I found an image linking to sims3updates is to make a reverse image search (right click > search google for this image) to see which website a particular cc came from.

Ninja'd again! XD

What I normally do when I want to browse Sims3Updates is copy/paste the sims3updates links into the Wayback Machine, like this:

http://www.sims3updates.net/details...at=cas&id=14913
https://web.archive.org/
https://web.archive.org/web/2014101...at=cas&id=14913
https://web.archive.org/web/2014071...at=cas&id=14913

It's been doing the same for me for several months now. I guess the site is no longer updated? You might be able to see it using the wayback machine. There are a few alternatives like http://mysims3blog.blogspot.com/201...mpothecary.html - which is about as old as sims3updates. I've not had luck with the downloads but use it to get an idea of what I'm looking for.
https://sssvitlans.tumblr.com/sims3cc is not updated anymore either but I have luck with the downloads, mostly.
For newer stuff try this https://pis3update.tumblr.com/ They don't have too much of the old stuff but once in awhile you will see posts for older cc. This one is pretty nice and new stuff is added every few days or so.

It seems like the site is up and running again, if it helps.

Oh, nice! I wonder why it did that in the first place, though?

It did that to me, too; the site's all over the place.