How do I get the circle to freely allocate points within it?

From Nothing Diamond with Dance with Death keystone on it.

From nothing jewel

There's a couple jewels with the modifier "Passives in Radius can be Allocated without being connected to your tree"

Like "From Nothing" and "Controlled Metamorphosis"

There is also "Entwined Realities" in the Oracle ascendancy.

... "allows the user to allocate unconnected passive skills within a medium radius of keystone passives they've allocated."

These connection less allocation areas can be granted through a few ways. namely certain unique jewels such as the “from nothing”, dropped from the king in the mists. Which will drop with a random keystone passive that it allows allocation around. The price can vary pretty widely depending on which keystone it is.

Another method is the following node after the “paths untaken” on the “oracle” ascendancy on the Druid, which allows something similar but for allocated keystones.

I believe there is also a unique jewel that allows allocation in a specified ring around itself but I am forgetting the name.

Amazon Twister slaps when you get it all up and running, this was a very good boost when I got this area set up!

Looks like druid feature with radius around notablles can be allocated