This may sound ridiculous and all but you can use Minecraft for it www,
some programs provide cg backgrounds you can rasterize and use, along with coloured background pictures. theres also many free images available. I know clip studio paint has the clip studio paint assets store where users make backgrounds and brushes for free ^^
I know lots of them r drawn by hand, but some of them look literally like it came out of a 3d sculpting like this one here http://iweb11.mangapicgallery.com/r/newpiclink/priscilla_s_marriage_request/1/1fea49073db572cf23ce10ff35951607.jpeg and here http://iweb11.mangapicgallery.com/r/newpiclink/priscilla_s_marriage_request/2/fb6f4538adf070a89b40596c4b71b3ee.jpeg . I tried drawing background but it took me heck ton of time lmao i could either give up my time to draw every background neatly or give up the quality of the drawing to focus on the whole story hahaha but good idea, i could take picts and put filters on them too! Thank you for your inquiry^^
aaaa i wish i knew how to minecraft wwwwww thanks for the inquiry tho!<3
ohhhh thanks! I'm using medibang, but if clip studio paint provides such assets i'd try them out! Thank you^^
I've also seen yuumei filter pictures she has taken herself into backgrounds in some speedpaints!
I've been reading lots of reincarnation manhwa and something with the kingdom and imperialism setting and i've been wondering, how the hell did they draw lots of nice western palace and buildings? I believe it must've been a template or atleast an app that allows you to design building and trace it as a drawing reference, but I don't know such app. Do y'all happen to know which app is it and where to find it? Or if you have tips for drawing background, i'll be so thankful as it's one of my biggest weakness. Thank you!