Hi Eliza,

Reply : In earlier versions of Odoo provides the option to enable the "Full Accounting Features" inside the Users form view.

But in V15 Odoo removes this option from the Users form View. In Odoo 15 if you can follow the below steps to activate the "Show Full Accounting Features".

Step 1: Go to Settings -> Users & Companies -> Groups
Step 2: Search for "Show Full Accounting feature" in the list view.
Step 3 : Open the form view of "Show Full Accounting feature", add users inside that and save it.

Full Accounting features will get activated for the Users whom you have added inside the group.

Regards,

Team Ksolves!