through
The first Nazi concentration camps were hastily erected in Germany in February 1933 immediately afterHitler became Chancellor and his NSDAP was given control over the police through Reich Interior Minister Wilhelm Frick and Prussian Acting Interior Minister Hermann Göring.[1]

what does through mean?
does it mean Reich Interior Minister Wilhelm Frick and Prussian Acting Interior Minister Hermann Göring.[1]GRANTED the controvl to NSDAP ?

how should I use 'through' correctly?

Question

through
The first Nazi concentration camps were hastily erected in Germany in February 1933 immediately afterHitler became Chancellor and his NSDAP was given control over the police through Reich Interior Minister Wilhelm Frick and Prussian Acting Interior Minister Hermann Göring.[1]

what does through mean?
does it mean Reich Interior Minister Wilhelm Frick and Prussian Acting Interior Minister Hermann Göring.[1]GRANTED the controvl to NSDAP ?

how should I use 'through' correctly?

Answer

In this context "through" gives the means by which some thing is done.
The sentence says that Frick and Goring were the channel by which the NSDAP had control over the police. As a matter of history, Frick and Goring were part of the NSDAP.