The ritual you’re asking about is called Ashta-Prakari Puja (the eight-fold Puja). Dhoop (incense) and Dipak (lamp) are two of the eight offerings in this puja. In many Jain communities this part is specifically referred to as Dhoop Puja and Dipak Puja and is performed to purify the space and inspire spiritual focus. There can be slight variations between Digambar and Shwetambar practices, but both traditions include dhoop and dipak as standard items in Ashta-Prakari Puja. You can read more about this practice in related Jain Knowledge pages.