As far as I’m understand the question correctly, you could add a formula field next to a number field that adds 1 to that number field. When you check a checkbox (or other trigger), let an automation copy the result from the formula field into the number field.
If you only want 1 number in a field, you could use an automation to put in its result. In the same automation “find” the field that has a number first to remove its value (input blanco) and then copy the number from the formula field of that record into the number field of the last checked record.
Example: New Recording - 12-7-2022 13:39:39
Automation: