The show is reasonably true to the comics. There are minor differences here and there, but it captures the essence and key moments of the comic book series pretty well.
It's reasonably faithful. The main plotlines and character developments are similar, but there are some minor differences for the sake of the TV format.
In general, the Umbrella Academy series followed the comics closely. There were some differences for the sake of adaptation, but the core plot and characters remained intact. Some visual elements and storylines might have been tweaked to fit the medium of TV, but it stayed true to the essence of the comics.
In general, the show has similarities to the comics, but there are noticeable differences. Some characters' arcs and storylines have been modified for better TV presentation.