Please don't ever wear all black to a wedding. It's often taken as a sign that you think the couple shouldn't get married - and that hopefully isn't the message you want to send. Wear a white shirt and a tie with a nice stripe or print. You don't have to dress like you're singing backup for Johnny Cash.
Yes, the all black outfit should be OK if you wear a thin white tie with it
If you do not got a dress code seems correct, if you want better Might try a white blazer and white heels
Do whatever you want. I think all black is fine to a wedding, there's no set code.
i read this assuming you were a girl but hopefully you're not aha, yeah like i don't see why a tie is necessary but a coloured tie might take away from the whole black thing a bit? like it's not a funeral haha