Hacking a gas bottle onto a dryer, indoors, is NOPE.
It's just depraved recklessness, and that's how the insurance company and district attorney will see it. Propane leaks are exceedingly common, and will create an explosive mix of propane and air while you sleep.
Now I gather you don't want your dryer outdoors. Well okay, there's plenty of precedent for having gas dryers indoors, and we have gold-standard ways of making the gas connections to normal hard line i.e. normal gas "black pipe". You simply use the same plumbing and materials you would use to plumb up a methane line in a utility-supplied house. Use gold-standard methods properly and you escape any charges of carelessness.
Separate the problems
But now, build a proper "shed" or enclosure for the gas bottle well outside the home - far enough away that any gas leaks will be dispersed and not reach flammable concentrations inside the home. Connect that with hard line into the home and to the dryer.
Now you have a simple matter of connecting the bottle to the hard line. That is routine stuff and you shouldn't have any trouble finding the kit for that.
Now you have "whole house propane" albeit fed from a 20 pound portable tank. It's just like a huge white tank from the propane distributor, it's just little. And portable. And the connections most at risk for leaks - where you're changing it weekly - are outside away from the house.
Can a 20 pound tank even supply a dryer?
Good question. Here's what we know: Dryers take about 20,000 BTU/hour. Radiant heaters, e.g. found in outdoor spaces at restaurants, take 20,000 to 50,000 BTU/hour. Those all use 20# tanks, so we can infer that the tank doesn't have a problem supplying a 20,000 BTU dryer, provided there isn't a "cold snap" out there.
The colder the tank, the lower the flow! It is vital to understand that. To vaporize in the tank, the propane needs to absorb a lot of heat from the surroundings because of its latent heat of vaporization. That's easy on a nice hot day, but you're asking in February.
If there is a "keeping tank warm enough to deliver BTUs" problem, they make propane tank heating jackets that are designed to provide supplemental heat when it matters.