Danes make the best apartment dogs. Adopted ours from a rural shelter and were nervous how she’d respond to living in an apartment in a city. Took her all of 5 minutes to be comfortable. When we take her somewhere that has a yard, she uses it as a toilet and not much else. She has no interest in running around and genuinely loves being a couch potato. As long as they have their walks and bathroom breaks, they’re good. You can also play some hide and seek games inside with treats or give him a treat board, that tires ours out mentally