#3
Well, I can't say it's good singing but I have heard much worse. I would suggest half a dozen real lessons with ta professional singing teacher should improve it alot - if you can't do that suggest you keep practicing and recording and listening. Your band should be able to help by adjust the scales to put songs in your range. They should also be able to tell you which notes you are getting wrong - those in your range are close.
#4
Id say you have decent pipes with zero training.  Get some training to hone your instrument and you might just have something really good.  Learning to sing well is exactly like learning to play guitar well.  Study, skill development, and practice.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#6
Do the gig, get the training.   

We are never 100% ready to gig it seems and there will always be some mistakes and some magic moments.  My 1st paid gig was at the age of 14 and I sucked pretty bad.  The whole band was pretty bad but this gig motivated us to get better.  We did.  We all got private lessons, we practiced together 3 times a week, and by the time we were 15, the band sounded like a real band.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY