If your wife comes with a tourist visa to Germany, she has to leave Germany before her visa expires. Because you only have a Duldung, there isn´t possible for her to get a residence permit for family reunion granted to live with you in Germany.
It´s not possible for you to be naturalized, as long as you just own the Duldung. To be able to get the German citizenship, you need to have a residence permit first. There is a possibility for you as holder of a Duldung to receive a residence permit in accordance to § 25b Aufenthaltsgesetz (Residence Act) granted. if you:
- have stayed at least eight years without interruption in Germany with Duldung, Aufenthaltsgestattung or residence permit (six years of stay for families with minors);
- cover the living expenses predominantly (at least 51%) by yourself (exceptions when in professional training, studying etc.);
- own German language skills A2;
- have not deceived about your identity and origin;
- possess a passport or are able to demonstrate you cannot get one.
After receiving the residence permit § 25b Aufenthaltsgesetz, you have to wait for eight nore years to be able to apply for the German citizenship.