If you have a US B1/B2 visa which is valid for at least 6 months from the date of travel, then you can get a 14 day visa on arrival for a small fee (this is what I did). Otherwise, you have to apply for a visitor visa, but you will get it pretty fast (in 1-3 days).
You have to show a negative PCR test result to board the flight in India (the sample should have been collected within 72 hours from the time of flight and the report must be a physical printed copy from one of the ICMR approved labs). Then when you land in Dubai, they will do another PCR test free of cost at the airport. You can leave the airport but must quarantine at your hotel until you get the results of your test, which you will receive in 24-48 hours (make sure your mobile has roaming, because you have to give them your mobile number and they will text you a link to the results; you can also access the results through PureHealth app but mobile number registration at the airport is mandatory). Once you get the negative result, you are free to leave your hotel.
Note that you might need to take a PCR test for your return journey. If you plan your trip well (whole trip duration <= 3 days), you might be able to use the Dubai airport PCR result for your return journey (this is what I did).
These were the rules 2 weeks ago, not sure if anything has changed. Check the Emirates website for the latest travel guidelines.