What is Sanatan Dharma? How old is Sanatan Dharma? Who created Sanatan Dharma?

God clearly says that this Sanatan Dharma is my form.

The literal meaning of 'Sanatan' is eternal or 'always lasting', that is, which has no beginning and no end.
The literal meaning of 'Dharma' is to adopt, that is, to identify the quality of that particular thing or person.

For example, the sky is eternal, and its Dharma or quality is sound.
The air is eternal, its Dharma or quality is touch.
The fire is eternal, its Dharma or quality is form.
The water is eternal, its Dharma or quality is taste.
The earth is eternal, its Dharma or quality is the smell.

Similarly, all human beings are eternal, their Dharma or quality is consciousness and service . While being conscious, a human being should see all the eternal, physical, and non-physical, universe with equal feelings and not with discrimination and should adopt truth, love, kindness, forgiveness, and friendship and live a virtuous life by performing Trisandhya, this is the basic element of Sanatan Dharma.

Just like air, water, sky, fuel (fire) and earth are eternal, in its view there is no difference of big, small, high or low, or caste. It gives its quality or Dharma to all creatures equally.

Similarly, the meaning of Sanatan Dharma is to always remain in the same quality for everyone or to see all creatures as souls and treat them equally.