Using FTP/ SFTP , or your web-host’s cPanel or whatever file management application your host provides, access phpMyAdmin on your host, then find your DB, there check the wp_options Table (Note: The table prefix of wp_ may be different if you changed it when installing), and make sure siteurl field and home field are correct. If you haven’t already done, always backup everything (including your database) before doing any actions, just in case something really goes wrong. You can never have enough backups!
If that’s correct, try manually resetting your plugins (no Dashboard access required). If that resolves the issue, reactivate each one individually until you find the cause.
If that does not resolve the issue, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel, navigate to /wp-content/themes/
and rename the directory of your currently active theme. This will force the default theme to activate and hopefully rule-out a theme-specific issue (theme functions can interfere like plugins).