One common theme is the moment of realization. It often focuses on Naruto finally realizing his true feelings for Hinata after the kiss, and how it changes their relationship.
Some fanfictions might have the first kiss happen in a more unexpected situation. For instance, Hinata gets injured while protecting Naruto, and when she wakes up, Naruto is so relieved and grateful that he impulsively kisses her. This not only shows his deep care for her but also how their relationship can be spurred on by intense emotions and life - threatening situations.
One possible plot could be that Naruto and Hinata are on a mission together. During the mission, they face a difficult obstacle that they can only overcome by relying on each other completely. After they succeed, the adrenaline and the new - found trust lead to a spontaneous first kiss.
You can try fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Naruto and Hinata Kiss' in their search bars, and you'll get a list of relevant fanfictions.