What happens to my iCloud photo storage, and corresponding photo storage if I delete images off my iPhone?

Hello,

I wish to free up space on my iPhone, by deleting a large number of photographs that I currently on my iPhone. However I am concerned that because it is connected to my iCloud photo storage, and from that it is then connected to my MacOS Photos application on my Mac Mini, that by deleting photographs on my iPhone Will also cause the deletion on both my iCloud for the storage, and the corresponding deletion of the same photographs on my MacOS Photos application on my Mac Mini, is that true?

Sincerely.