A number of people here have talked about using a dry box with a few packets of desiccant thrown in, but could I suggest that you use a “Damp Trap” - available from Dollarama & Dollar Tree?
The product is design for keeping an area dry in a basement, but it really works well in a dry box. I just throw it in and check it periodically to see if the desiccant has been used up and if it’s full of water (when that happens, you pour the water out, put the box in recycling and put in a new one).
I have two primary dry boxes, one that is for PLA with different colour spools that are moved in and out fairly regularly and one for ABS and PETG that is opened quite infrequently (I use ABS & PETG for structural pieces, so I tend to print in grey and run them to the end of the spool). I’m saying that because the Damp Trap in the PLA box does get filled up with water over the course of 6 months to a year while I’m still on my first Damp Trap for my ABS/PETG box with only a cm or so of water on the bottom and lots of desiccant still available after two years. Of course, YMMV.
Yes, the cost of a “Damp Trap” is $1.25.