Equity fund is a part of index fund hence both have their pros and cons. Equity funds are the most popular due to the past performance of these funds. You can select both by dividing your investment with 50-50.Equity funds provide various types like large cap, multi cap, mid cap, small cap, hybrid, elss whereas index funds are kind of sectoral funds which are kind of risky funds. Since you are opting for sip mode go with equity funds and you can go with index funds for lumpsum investment. In index funds also go with nifty 50 index or you can also go for etf option. ETF are the best way to invest in index funds rather than going through regular index mutual funds. You can refer Infini mf app for top performing mutual funds.