Kateikyoshi no Kishi Knight desu.

both of these are cute and light-hearted series about a silly and ridiculous delinquent who starts getting tutored by a kind and mild-mannered older guy. all about slowly sparking a change and moving towards a specific goal. neither is too overt in their romance aspect

Uhh they are both bl and I cannot reach you has a tutoring element but it isn't like a parody of anything like that

One of the actors in I'm private tutor kishi naito is also in school trip as one of the friends in the group, school trip is also a bl and set in high school

If you are looking for blonde delinquent with a softie inner self, these dramas have both. Being adaptations from a manga, they have anime-like kind of acting which is eccentric to see IRL but the actors in both pulled it off. I already knew it since the MLs in From Today, It's My Turn!! have an established name in the industry but Kateikyoshi no Kishi Knight desu has relatively new faces but if you are doubting, you should give it a try. The story is simple but so promising.

Both Japanese boys' love dramas with eccentric, shonen manga-esque leads who have crushes on their teachers. Having similar story premises and comedic tones, you may enjoy one if enjoyed the other.