Yes, you can swap cartridges as needed, but some ink will remain in the printer’s internal ink path/print head, so the change won’t be perfectly immediate. There isn’t really a way around that except using a separate print head or effectively a second printer.

If you switch between third-party and Canon inks, expect a little carryover at first. A cleaning cycle may help, but it also uses ink, so doing it often can reduce the savings.

If most of your printing is documents—especially black-and-white—a better long-term money-saving option is usually a monochrome laser printer. Laser printers typically have a much lower cost per page for text documents than an inkjet, while you can keep the Canon for photo printing.