Help with a Joomla upgrade (3.10.x to 4.x)?

I support a web site, https://rockridgencpc.com, which I didn't build; I certainly didn't select Joomla.  (My personal site is WordPress.)  I inherited it from a previous volunteer.  I've figured out how to format it and work with it, but I don't normally mess with it much.  I'm facing the need to update from v. 3.10.11 to 4.x, before August 2023.  I've started research, and there's a lot I don't know - how to tell if my extensions are 3rd party, whether the theme I use is compatible, etc.  I need help.

I've tried several times (some years ago and again just now) to log in to the Joomla Forum site, https://forum.joomla.org/.   It recognizes my userid, but it says I've exceeded the login limitation (the first time I tried in years!), and it insists that my password is incorrect (even after I change the password).  I can't log in.  It says if you keep having this problem, please contact the Board Administrator - and when I click on the board administrator link, I get "The board administrator contact page has been disabled."  Does anyone know how to get into that forum?  Can anyone here help me?

Again, very helpful, thank you.  I think I just found something much like it in the help files at my ISP, Siteground.  I'm feeling much better about this, and will feel even better if Joomlashack tells me my site theme can upgrade to Joomla 4!

Unfortunately, Joomlashack says my current theme, js_novitas, will NOT upgrade to Joomla 4.  This means I have to find a theme that runs on Joomla 4 (which apparently won't come from Joomlashack, there's nothing on their site about Joomla 4 themes) and redesign my web site around it.  And that means i have to build a test site - I don't want to be playing with theme design on a live site.

I have the drive space to put a copy of my site on my Windows 10 laptop, which has 8 GB of RAM and a 64 bit processor.  Can you suggest the best web hosting software to do this?  Years ago I used WampServer but I don't recall any of the details.

Thanks; I've found my 10 year old notes about using Wamp Server last time, so I'll work with that.

Can ANYBODY tell me how to reach someone at Joomla.org to deal with the fact that there's something wrong with the login?  I've created 3 different logins and every blessed one of them fails, and has ALWAYS failed.  You're supposed to go to a page (I think it's Domain Administrator) - but the page has been removed.  I'd love to be able to ask questions in a Joomla forum but have never been able to log into the site.

This would be very helpful, except that I would have to log into the site to use the help desk, and my problem is that I can't log in.  It actually accepted one of the 3 ids that exist, none of which work, but when I tried to use that ID to log into the forum site, I got the usual error.  And as usual, the Board Administrator page is disabled.

You have specified an incorrect username. Please check your username and try again. If you continue to have problems please contact the Board Administrator.

I guess it's hopeless. Thanks for trying.

I can't believe it after all these years, but I've solved the problem of my Joomla forums login!  First, I didn't realize till recently that Joomla rejects special characters in passwords, which I use as a default.  Second, I spoonerized the userid!  I sent a "forgot my password" request last night to Joomla forums, using my mindspring.com email address, for a login I thought was hedera64.  This morning (they're in England!) I got the link for a new password - for a login for hedera46.  I can now log in.  I am SO relieved!

Now you can see if you can get your username fixed for the forums.

No, I've identified the valid username, it's hedera46 - I apparently mistyped it at some point.  I can log into the forums.  Phew!