The employee grouping for account determination

Dear experts!

Now, I'm getting some issues about The employee grouping for account determination.

- The first, when I define Employee grouping for account determination, after that I want to know How do I can assign Employee to Employee grouping for account determination.

- Second, where is I can assign employee group, employee subgroup to Employee grouping for account determination?

Help me, please!

Regards Huy!