That's only a question when you conpletely ignore history and pretend that nothing happened before. Terrorist don't jsut pop up randomly. They are created by circumstances.

You shouldn't ask "what's the solution to a terrorist group embedded in a civil population". Your actual question should be "What did we do to create that problem and how could if have been prevented?". Even if you only ask that to not do the same shit again...

And in Israel's case the answer is very easy. They could have worked on peace and independence of Palestinia 30 years ago, like it was planend when the National Autority was created to gradually do that. Instead they spend more than a decade on being happy with the status quo of an occupation they don't even had to pay for as that was covered by international partners... until Hamas got a majority in 2006. Then they could have supported the peaceful government in their fight against Hamas ~15 years ago. Instead they watched cheering for Palestinians fighting other Palestinians... until Hamas controlled Gaza. And then they could have still spend more than a decade of limiting Hamas' influence. Instead it was Israel's government that used Hamas as an excuse to to show the National Authority wasn't speaking for all Palestinians and so they wouldn't need to work with them for any peace.

30 years of bullshit and then asking "what do we do about Hamas?" when the real question is "why did we create Hamas like it is today and why are we still continuing the exact same course?".