Every Indian mutual fund you hold is, to the IRS, a Passive Foreign Investment Company. That means a separate Form 8621 for each fund, every year, and a default tax regime built to punish deferral. Most people find out years in. This tells you where you stand.
Count each fund separately, not each SIP instalment. Three SIPs into one fund is one PFIC; three different funds is three.
General guidance only, not tax or legal advice. This is an exposure check, not a computation of tax. The section 1291 calculation depends on your full holding history, each year's distributions and the top tax rate in each of those years, and produces a figure only a preparer with your records can give you. Form 8621 filing thresholds and exceptions exist and are not applied here. Nothing you type leaves this browser.