Yes, having a boyfriend at the age of 12 is considered haram (forbidden) in Islam.
While the reference provided is brief, the general Islamic understanding prohibits boyfriend/girlfriend relationships at any age due to the potential for actions that are considered impermissible, such as physical intimacy or even prolonged, unsupervised interactions. Islam encourages modesty and refrains from situations that might lead to temptation or un-Islamic behavior.
The reference also highlights the permissibility of respectful interactions with the opposite gender in appropriate settings, such as school. This includes showing kindness, being polite, and maintaining appropriate boundaries. Such interactions are expected to be respectful and avoid any actions that could be considered inappropriate or haram.
In summary, dating or having a boyfriend/girlfriend is generally considered forbidden in Islam before marriage, regardless of age. Proper conduct, respect, and adherence to Islamic principles are emphasized in interactions with the opposite gender.