I am from India. Can I visit the Taj Mahal for tourism?

First: Traveling for leisure is permissible, and the default rule for customs is permissibility. Traveling to the Taj Mahal for sightseeing is permissible. As for the tomb it contains, the tourist does not intend to visit it with the intention of worship; rather, the intention is to see the palace, and the tomb is merely incidental. What is forbidden is undertaking a journey specifically to visit the tomb, or to attend innovations (bid'ah) there.

Second: The permissibility of travel is conditioned on the absence of forbidden mixing or abominations in the place that the visitor cannot change or avoid. This is because the servants of the Most Merciful "do not witness falsehood, and when they pass by something vain, they pass by with dignity." And whoever intends to go to places of sin or to watch their people without denouncing it, is a sinner.