The German national category D visa is more or less given to you to enter Germany and apply for the residence permit. Then it depends on which residence permit you will get.
Also, for your spouse to work in Germany, he/she should get first a visa, and then the residence permit and work permit. Usually, in such cases, he/she can apply for the visa and later for residence permit for the purpose of the family re-union. However, he/she can also apply for the other types of visa / residence permit (e.g., for the working purposes).
In case if he/she gets the residence permit for the purpose of the family re-union, and if you will have the residence permit for the purpose of employment or Blue Card EU, your spouse should get the same work permit as you (e.g., if the enterpreneurship is allowed/prohiited for you, the same could be for your spouse).