I'm wondering if this game runs smoothly or not on a modern computer. If it doesn't work well, what should I do to make it work okay?

Arcanum has always been very buggy. I've been playing it with the unofficial 2.0 patch by Drog. I've not seen any issues so far.

www.gog.com/forum/arcanum_of_steamworks_and_magick_obscura/perfect_arcanum_on_windows_10_fullscreen_or_window_ 1

Try the instructions in above thread. the unofficial patch UAP is essential for fixing a lot of bugs but doesn't seem to help it run smoothly.

For Win7 and 8, the 3DAnalyzer program might work, but requires some trial and testing. Also rename the ddraw.dll file in the game folder(i think) to increase loading speeds.