If you're unable to choose or add a check layout in the Invoicing/Accounting Settings of Odoo, it could be due to a few possible reasons.

Check User Access Rights: Ensure that you have the necessary access rights to modify the Accounting Settings.
Verify that your user account has the appropriate permissions to access and modify the check layout settings.

Verify Installed Modules: Confirm that the required modules for check printing are installed and activated in your Odoo instance.
The modules related to check printing are typically part of the accounting or payment-related modules.
Check if there are any available updates for the installed modules and the core Odoo system.

Check Module Dependencies: Double-check if the check layout functionality is dependent on any other modules.
Ensure that all the necessary dependencies are installed and activated.
d. Choose the payment method associated with check payments and ensure that the "Check Layout" field is visible and editable.

Hi,

If you are using community edition, by default you don't have the option to print the check from the system. If you are enterprise user, you can install check layout module according to your country from the apps menu.

If you are community user, you may have to rely on third party app's which provides this functionality or built one check layout by yourself.

Thanks & Regards

Walnut Software Solutions