You're both spewing talking points and talking past each other. Hamas are an extremist militant reactionary force to a colonial occupation. To directly address your talking points, they are both supported by the general populace in Gaza and holding them hostage at the same time. How? Because they do horrible, brutal things that no one likes, including to their own populace. But that brutality is at the same time seen by the imprisoned populace as the last option of resistance against the brutal occupation by force that they're all under. Because they marched peacefully for years and were met only with bullets.
Decades of moderate negotiations, as represented by the PLO, have not just gotten Palestinians nothing, things have actively gotten worse in that time period, with hundreds of illegal Israeli settlements going up for hundreds of thousands of people. Not even in the chaos of Gaza that everyone points to, but open naked land grabs in the West Bank. The peaceful, collaborating West Bank, where if you're an Arab Muslim, born and raised there where your family has lived for centuries, you can't travel or work because you live behind giant walls erected by illegal occupiers who corral you with one of the strongest militaries on Earth. Every five steps an armed checkpoint full of conscripted soldiers who hate you because of your ethnicity/religion and do everything they can to mess with you and spit on you and make your life worse. Why? For one very simple reason. You are not them. So they want you to leave. And they'll do everything they can to get you to.
This is a very long, very complicated, intractable conflict. It is not a good guy/bad guy simple situation. Both sides have burned civilians alive for no other reason than being who they were. The ANC carried out "necklacing"(putting a tire around someone, dousing them in gasoline and lighting it) on apartheid collaborators in South Africa. Belfast had the most bombed hotel in the world at one point because of the Troubles. Humans are a violent species and our struggles are violent. We dropped the bomb on Japan(and mass bombed civilians throughout Europe before that).