There are multiple talks and writings on the subject available at https://auromaa.org, you can search there.
Very briefly, Sanatana Dharma is a many-sided approach
In the pure Adwaitic sense they are one but not necessarily the same. All is the One Reality but covered with Ignorance. That is why
Yes it is a good way. Explaining to someone else is different. It requires a different faculty. It is enough if you feel something understood.
One doesn’t become a Hindu just by being born in a Hindu family. One should be a dwij, twice born, born into the spiritual life
