??? Of course you can.
Your comments sound like you installed KDE ontop of a distro that uses gnome by default, missing half the packages.
KIO exposes pretty much every possible protocol (including smb, dav, ftp/sftp/ssh, etc) to every KDE app, including Dolphin, Kate, Gwenview, Krita, Okular, etc.
If you're trying to open SMB files in Gnome apps, ofc, that's not gonna work.