As you have made changes both through your dashboard settings and phpMyAdmin because of which your site does not work, you need to reverse those changes. Only you know what you changed. None of us here know what was changed. So, try to remember what changes you made and try to correct them. That's the only way you can restore your site (local or online) because you do not have any backups.
Again, it is a huge mistake that we do not create and store safely backups. Even when we do not make any changes, sites can have problems because of unexpected reasons. If we have backups, we can always restore our sites safely and immediately. So make it a habit to create backups, especially when making changes, upgrading software, moving sites, etc.
Any assistance would be appreciated more than you can ever imagine.
Yes. We would love to provide assistance. But for the above reasons, how do we know what went wrong, and if we do not know the problem, how do you expect us to suggest solutions?
What I suggest is, remember what you did and try to make amends. While doing so, if you find specific problems, ask here.
Better yet, if it is a new site and you do not have any contents to lose, why not start afresh?