We barely understand gravity according to theoretically physicists.

We used to have Newtons theory of gravity but the model was upgraded by ein stein with his theory of general relativity.

Which basically says massive objects bend space time causing pockets of gravitational pull to form.

However, this theory according NASA requires the universe to made up of 70% dark energy and 25% dark matter.

After last few decades we still have no evidence of dark energy or dark matter.

So no the theory of gravity is not settled at all.