Edit the value in another table

[demo_demo]

I am having table department
Department table holds the column Dep Code and Dep NO ID as number data type
I am having another table has Members
I am having the department column as text and i am using select expression in suggested value
When i create a row in the member table with select one of the department code
I need to increment the value of Dep No ID in the Department table with +1 only if the Member Department = Department code
Suggest any expression??