Peter Parker's reaction was one of determination. He was motivated to do more to prevent such tragedies in the future and was driven to be a stronger hero. His emotions were a mix of grief and a resolve to make a difference.
Peter will probably be very confused at first. He's used to being part of the team, and suddenly being hunted by them is a huge shock. He might try to talk to them to clear up any misunderstandings.
Peter would likely be defiant. He has a strong moral compass and wouldn't easily give in to Osborn's demands. He'd probably try to find a way to escape right away, using his spider - abilities like climbing walls and his super strength to break free from any restraints.
Peter would probably be scared at first. He's just a kid, after all, and being kidnapped by a powerful being like Thanos is terrifying. But he would also be defiant. He has a strong sense of responsibility, so he might try to find a way to escape on his own.
First, if the fanfiction is really good, you can recommend it to your friends who are also fans of Peter Parker. You can react by being critical too. If there are plot holes or if the character of Peter seems out of place, you can write a constructive review. Another way to react is by creating fanart inspired by the fanfiction. This shows your appreciation for the story in a creative way.
Peter usually blushes a lot. Since he's a shy and somewhat awkward teenager, his face turns bright red when the Avengers embarrass him. He might stutter while trying to defend himself or come up with an excuse.
Since Peter is Spider - Man, he has to be careful not to use his powers and reveal his identity. So he might just try to defend himself in a non - superhuman way, like using his quick reflexes to dodge Flash's blows as much as possible while trying to calm Flash down verbally.
Well, in fanfiction, his classmates' reactions can vary widely. There are those who are his friends and they would be supportive. They might cover for him when he has to run off to be Spider - Man. On the other hand, there could be classmates who are envious. They might spread rumors about him or try to expose his secrets just out of spite or envy. And then there are the classmates who are just indifferent. They don't really care about Peter's secret life and just see him as an ordinary classmate most of the time.
The Avengers would initially be in shock when they find out Peter is sick. Clint Barton would be the one to keep a calm head and start organizing things. Wanda Maximoff would try to use her powers to ease Peter's pain if possible. Vision would use his vast knowledge to try and find a solution. They would all be very concerned and do everything they can to make Peter better, from getting the best medical help to providing a safe and comfortable environment for him to recover.
Some Avengers might be initially skeptical. Thor, for example, might not understand the power of a 'spider - boy' at first. But others like Captain America would probably see his potential and welcome him. Black Widow might be intrigued by his skills and try to train him further in espionage - related aspects.