Is meyve "fruit" as in a category (compare to German Obst, for example) or a specific single piece of fruit?
it's just Obst. It can be an apple, orange, melon etc.
I jusy met you and this is crazy but here's my number, so call me meyveyi.
Why in someplaces.. it says siz and here it says sen??
siz is plural or formal you, sen is singular informal you
"Sen" means you (sing.)
"Siz" means you (plu.).
But somewhere "Siz" means "sen" to show respect the one you talk to. Like "Sie" in German
Or aap in Urdu
what is the meaning of this yi on the end of the word?
für was steht das yi am ende des Wortes?
It is the accusative case. This is used when you have a specific direct object.