wp-admin redirecting to my sites homepage.

You may want to deactivate all plugins and then re-enable them one by one.
This should help you isolate where the code is coming from that is causing the redirect.
You should check if you have any items in the mu-plugins folder as well.

I have tried that, however (deactivating the plugins then reactivating one at a time, though I did not need to add but one plugin (woocommerce), and this issue started again immediately.

That said, you have piqued my interest by asking about the mu-plugins. I was looking at my plugins, and I did find that I have a mu-plugin. I do not know what this is or where it came from. Can you please help me understand what this is, what it does, and should I get rid of it? Though I will be honest, since I do not know what it is or how it got there, I have no clue how to get rid of it if I need to other then to rename or delete that folder or its contents. I am not sure what was installed that put it there.

I am hoping that you tell me that its something simple to deal with.

Thank you!

I noticed that the mu0-plugin was for Affiliate Programs or for WooCommerce Multivendor Plugin Support, either way, I don’t need either of those. I also know that the plugin I found recently was found to have a security vulnerability, so to be safe, I renamed it, which deactivated it, I recreated my Auth Cookies by regenerating the salt params and installed some Security plugins to keep my site safe, I have had no negative impact from deactivating the plugging and I was able to get my wp-admin to work again.

Thanks for pointing me in the right direction! ?? Cheers!

Really glad you managed to solve your issue.
Also, thank you for marking the thread as resolved and confirming a solution.
That really helps others who face similar issues to find this thread more easily.

So, in short, MU plugins started for Multi-Site networks, but their uses expanded over time.
These plugins are not subject to the same update processes as normal plugins and cannot be deleted from /wp-admin/, which is why some security plugins keep certain backup data in them, for example.
They are great for small, custom-written plugins (so plugins that you wrote yourself and are not hosted in the plugin repository).
The way to delete an MU plugin is by logging in to your hosting panel and using File Manager (or your host’s equivalent) to remove the file, or to do so via FTP.