Typically, these fanfics often focus on their relationship, whether it's friendship or a budding romance. They usually incorporate elements from the original 'My Hero Academia' universe, like their hero training and the challenges they face at school.
One common theme is their mutual growth. They both are on the journey to become great heroes, and fanfics often explore how they inspire and help each other to grow. For example, in many fanfics, Uraraka's positive attitude helps Deku when he's feeling down about his progress.
In deku and uraraka love fanfiction, the development of their relationship is often slow - burn. It's not like they immediately fall in love. Instead, it starts with friendship and respect. There are a lot of small moments that build up the tension and the connection between them. Moments like when they train together, or when they save each other during battles. These moments are then used to gradually show the deepening of their feelings for each other.
Yes, there are quite a few out there. You can start by looking on popular fanfiction websites like Archive of Our Own. Just search for 'Deku and Uraraka kiss' and you'll likely find some interesting stories.