Story Quests vs. Endings I am EXTREMELY confused. So I see the 18 endings..

Question for Harvest Moon: Hero of Leaf Valley

Story Quests vs. Endings

I am EXTREMELY confused.
So I see the 18 endings, and ''there's 3 Story Quests you have to see before Winter 30 year 2".... The endings aren't story quests?

For example, I am following this guide.
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8.6. The Tale of Blue Bird [E86]
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The Tale of Bluebird is also known as The Blue Bird of Happiness ending.
The main leading character for this ending is Aurellia.
It started when you pass the cafe and you heard a beatiful music played by
Someone using ocarina, later you found out that it's Aurellia. The music played
Supposedly able to attract the Blue Bird, and they said it bring happiness to
Anyone who sees it. Will you be able to put a good performance and call the
Bird?

1. The sound of Ocarina
Location: Cafe/Bar Area
Time: Summer 16- Summer 21, Year 1. Any day except Monday.
Requirements: Be friend with Aurelia (20FP)

2. An advice to buy Ocarina
Location: Sun Garden Cafe
Time: Summer 26 - Fall 1, Year 1.
Requirements:Triggered after you have ocarina.

ETC. Are those ('1. The sound of Ocarina" and '2. An advice to buy Ocarina") the story quests????? There are 16 of them for that ending.. Wouldn't I have to do all of them for that ending?