India’s spend on the Military budget is roughly $40B or roughly 2.3% of the GDP. (Brazil spends 1.4% of its GDP or ~$25B, with no threat from any of its neighbors. China spends ~$215B and Pakistan ~$8B).
Roughly 58% of India's spend is towards pay and pensions for the personnel which goes towards employment generation and boosts the economy.
Spending on military gives the following advantages :
Military spending guarantees national security and goes a long way to portray stability in a country. Foreign investors
desire stability to invest in India’s (or any country for that matter) infra and energy projects. Think about Iraq or a Libya, countries with vast oil resources to exploit. Do these country attract investment from other countries? No!India doesn't have a veto in UNSC. Signing import deals (India spends a lot on arms imports!) from countries with veto ensures that the importing country’s interest are protected in the international forums (though this is might not be stated quid pro quo, but this definitely helps in negotiations.)
India aspires to be a regional/super power. For any country to influence any regional or international policies (Gun Boat Diplomacy) it needs to develop soft as well has hard power. Soft power being the perception of the people around the world - be it cultural or regional. Hard power can only be demonstrated by building a strong army.
Not to mention, the armed forces are always ready to carry out evacuation & rehabilitation activities during any natural disaster and internal disturbances.
It would be.... if the money was going to domestic production and innovation. How much of India's defense budget is spent on imported weapons, technology, and equipment?
A significant portion. India hasnt built the capabilities enough to produce such high end weapons in house. Though it is working on various technology transfer initiatives, it will take decades to be self sufficient.