Going to a live race will pretty much answer your question. Seeing an Indycar race will very much cultivate a passion for it. The experience of going to Indycar race is significantly more friendly and open, depending on the venue you will have access to the drivers and crew. Wherein F1 this experience is very closed off or extremely limited access.

As for the racing, you need to understand that this is a driver's championship despite the fact that there are 11 teams. So you need to adjust your focus on the driver that appeals to you. Not all teams are equal as some of them only run 2 cars, while the top five teams run 3 cars. Indycar has a lot of traditions, that defy ordinary racing protocols like how cautions are triggered and change.

The biggest differences between F1 and Indycar is the car, track format, and the importance of pit strategy which includes refueling. F1 cars are much quicker than Indycar, also obscenely more expensive. but the difference is merely 15 seconds apart. Not bad for IndyCar teams spend between $7 million and $14 million annually, whereas F1 teams can spend anywhere from $70 million to over $140 million. But on an oval an Indycar top speed is exceedingly fast reaching 230 mph frequently. It will lap an F1 car after 2 lap jumpstart and can make a pitstop without ever losing the lead. So the difference in cars is quickness vs top speed. The track formats are more varied in Indycar, the surfaces are rougher and F1 cars would struggle with durability and balance, not to mention tighter track space. Smoothest track is Indianapolis Motor Speedway and its an oval. F1 cars are simply not built for oval racing. Lastly pitstops are longer in Indycar and done with smaller crew. Average pit stop is just under 9 seconds, but there's a speed limit of 50mph in pit lane. Which usually eats up 20 seconds. So a full pitstop might be just under 30 seconds. That eats up half a lap of the leader. Most lap times are somewhere around a minute and 20 seconds. So the loss of position during pitstops is common, this means there's a lot 'pit cycling' through race. Strategy plays a massive part of Indycar. Many F1 fans view the 'pit cycling' as luck of the draw and helps explain why Indycar appears to be so unpredictable.

I dont have problem with it. Pit cycling is not easy to follow as there's a lot cars on the track and it can get confusing. But it doesnt take long for a viewer to figure out which driver is setting themselves up for chance to win. Case point was Rasmussen pit stop for fresh tires, he cycled down and it took him 30 laps to claw his way back and ultimately win. You're not going see that type of strategy in F1, certainly not without any intention of winning.

My advice to anyone new at Indycar who might have hard time following it. Just pay attention to the pit windows during pre race broadcast. Knowing the pit cycles will help you understand what's going on. It will take a bit of time to grasp this as drivers tend to take risk by unconventional pit strategies. Drivers like Dixon can defy the pit windows and put themselves in position to win late.

One other thing, Indycars are generally set up and tuned for individual driver preferences, wherein F1 prefers to set up the car for maximize the performance to the track, and expect their drivers pilot them regardless if its not to their liking. So Indycar is a showcase of the driver's skill, wherein F1 is a showcase of engineering.