You should register to ARBİS https://arbis.tubitak.gov.tr/ .
You should contact arbis@tubitak.gov.tr .
For national applications, you do not have to because TUBITAK will calculate during negotiation.
However, for international applications, you should fill these parts as a formality according to the rules stated in the budget form.
Here is the official explanation in Turkish. Please contact us if you need help.
According to the current rules of 1001, here is the table:
You should proceed by following the steps on the application system.