I always end up in decision paralysis because I think of way too many possibilities. Is there a way I can avoid brackets? If I am able to drill into studs should I just use normal wood screws? I’ll be using it as a tea/spice shelf.
This is good advice. OP, use studs, not anchors. I’ve never had good luck using wall anchors on drywall.
if the spacing doesn’t work for studs, another option would be to use angle brackets hooked to the shelf and into a stud (optimally two studs).
If the unit cannot span two studs, center the unit on one stud and put an angle bracket on each shelf into the stud, then anchor the corners using drywall anchors - the brackets should take care of most of the weight and I would think the drywall anchors would hold and provide stability.
If the unit can span two studs, center the unit over those studs and do the same, attaching angle brackets under each shelf. At that point you can skip the drywall anchor rigamarole.
Of course, the angle brackets would end up being visible, so you may want to paint them or camouflage them in some other way.
If you can only hit one stud, you should hit it in two places vertically if possible. Bottom shelf and top shelf if you can. You can still add some anchors if you need, but that works for most things. I hang cabinets into single studs all the time just by screwing it in two spots. It will work as long as the shelf or cabinet is built well enough.