Iphone 6 won't charge? - 1

My friends iPhone won't charge, it can't be a problem with the charger because she's gotten through at least 3 different chargers within a month. Does the phone need replacing or could it just be the battery that needs replacing?

IPHONE 6 BATTERY DRAINING

So I charged my battery to 100 and it dropped to 79 in 28 mins, do you think it's ok? Should I change the battery? I bought it used yesterday the shopkeeper will replace it with any other iPhone 6 in the shop, what should I do.
Please SHARE YOUR BATTERY EXPERIENCESSS

Is it stupid that I randomly cry when i'm alone over not having the phone that i want?

I'm stuck here with a LG that i have had since year 8 when all i'm asking for is the iphone 5 I don't understand why my parents will not get me the phone i'm asking for. Its not like i'm asking for the iphone X i keep randomly crying i think i'm getting depressed because all my friends around me have the iphone 7 and 6 and being in year 11 it super embarrasing to have an LG when i'm quite well known at
school this might sound dumb but I don't think I look the type to have an LG.

Added (1). I mean the 5s

How would you know if someone has blocked you?

I'm not on speaking terms with this person at the moment. Without calling, is there a way to know if he's blocked me? I have an iPhone and he has a Samsung. So when I text him, even if he gets it, it never says "delivered"

Help resetting iPhone 5s?

So I have an iPhone 5s and I haven't used it for two days because I was away and very busy. But now I have forgotten my password and I don't remember my Apple ID. And I did not connect it to iTunes and icloud. So I'm I'm a horrible situation not knowing what to do. So are there like any buttons I can hold and press to make it go into factory mode or something like that? Because I need this phone and can't buy a new one yet. Please please help and remember this is an iPhone 5s.

Should I buy an iPhone 7?

I currently have 1505 dollars and I really want to buy a new phone cause the one I have is **** and I'm 16 but I'm scared to tell or ask my mum if I can buy it because she might not approve. Someone help?