Like what brand
An easy way is to use potassium chloride. I use Mortons lite salt (it’s a 50/50 mix of potassium and sodium salts). I believe Nu-Salt or NoSalt are just potassium chloride. You can find these in the aisle of your grocery store where the salt is.
Like the other person said, get the No-Salt potassium chloride. Potassium supplements are scams and they legit have like no potassium in them. I think the biggest they can go is 100mg, which is nothing.