@Uncle, as a start - you have switched to php8 and your TB code version is build for 7.4. You can fix that in coreupdater's settings by choosing the proper version or simply leave it to 'server's version' and check for core updates after every php switch.
Please, install error collection module that is shown in your module list and check what error is given there. (you might see some notifications in connection to php 8.0, nothing to worry about if it's not an error.