Q1: Which name is best: ISIS, ISIL, Daesh or Islamic State etc
A: The article title is decided according to policy WP:Article titles

The discussion that resulted in the current name Islamic State was held in August-September 2021. The decision followed WP:Commonname section of WP:Article titles.

This question has been raised over 40 times on the talk page, without any proposal other than the September 2021 and August 2013 discussions resulting in a page move. Now archived, those discussions can be read here and searched here.

Past names, both used and considered, have included: "Islamic State of Iraq and Syria", "Islamic State of Iraq and (al-)Sham", "Islamic State of Iraq and Greater Syria", "Islamic State", "The Islamic State", "Islamic State (Middle East)", "Islamic State (Organisation)".