The Usual Three:
1. Verify fuel pressure at prime, at idle, and under load. Make sure the fuel filter is not plugging. New-to-you vehicle? Might as well replace the fuel filter, along with ALL the other fluids and filters except for A/C refrigerant/desiccant IF the A/C actually works.
2. Assure all "tune-up" parts and procedures are in good usable condition. Distributor cap, rotor, plug wires, spark plugs, PCV system, EGR system, EVAP system. Check initial spark timing, electronic spark advance, verify cranking compression, and look at the heated-air intake. Replace the O2 sensor. Avoid cheap-junk parts from Amazon and others with brand-names that look like a bunch of letters strung together at random.
Buying from a local parts store is more-likely to get you parts that AREN'T counterfeit.
3. Connect a scan tool, verify EVERY sensor, and computer output including IAC. Check fuel trims just before, and as the engine stalls.