depending on the size of the city I'd recommend drawing a small portion of city buildings as a section and
pretty much copy and paste those same buildings into different areas of the image (that is being crushed by a macro) and can also flip the section of buildings around to make them look different
and what I would do is add little details like satellites or antennas to make them look different but still be the same
of course, this idea might be hard for "perspective stuff
I'm no artist at all but something I'd try
or maybe make a folder of buildings you could paste in different arts you draw so you're not constantly making new ones you can just open a folder, drag it to the art modify it how it needs to fit and boom :3

That you for the help uwu

i've seen some friends make a city brush that anytime they need quick cities with not much details they use that

or using a pre existing city drop and editing it with new structures or having it used as a reference for new ones

Thank you for the advice ^^

I know some people use images from Google earth greyscale it then brush it into a picture or something similar to that

Thanks for the advice! Just to clarify, what do you mean by brushing it in?

Apologies may not have got the terminology 100% correct. Just going from what some artist friends have told me. They take exports from Google earth use edge detection filter then patch it together and "paint" it into the background. I think

Ooh, that sounds like a really good method! I'll try to incorporate it into my next piece. Thanks for the advice ^^

I won't lie to you that I would also like to learn easier methods, drawing details like this takes time and sometimes it is more time consuming because of how complex it can be to generate the feeling of detail. What you can do is if your program allows it, put rulers, or perspective grids, allows you to draw straight lines in your drawings.

Another thing you can do, and sometimes it is convenient is to look for images of real buildings and edit them or draw over them, whether you like photobashing or not, you can create more detail.
Several brush sets already come with details of buildings like windows, doors, railings etc, some of them are free.

Another technique that you can use, is to dedicate some time to detail the main or close aspects and everything else give the background, or far away fill it with multiple lines, it doesn't matter if they are not so clean or straight, what matters is to give the "sensation of detail" instead of "adding detail", I don't know if I explained, but I hope I could have helped you in something :3

Thanks for all the help, I appreciate the advice ^^

I think I can understand the kind of detail shortcut you're talking about! Kinda like on uncolored line art/sketch, drawing a texture on everything would make things look too busy, but having just a few patches of bricks/scales/grass here and there can let the mind fill in the blanks. I've seen some nicely drawn cities that are just a few tall buildings in the middle of a plain gray grid.