some people will tell you that you can just put yellow tape in your existing rims, but I never made it work.
IME non tubeless rims require a rubber rim strip, this effectively puts the bead of the tyre in contact with the rubber and the sealant sticks it together
A proper tubeless rim is shaped so that the bead sits tight against the rim and will seal with just yellow tape.
proper tubeless rims seal much more easily and also much easier to get tyres on and off. the only question is can you afford to re-rim your wheels?
edit – just to add – yellow tape needs push in valve, rubber rim strip has valve attached