The stage thing is something you will either love or hate, irrespective of your voice.
If you are learning to sing without any input from a friend or teacher you trust - then it is hard, but one thing you need to do is find music to sing that gives you a start. From your examples - your pitch in general is OK, but you have trouble going from one note to another when the interval is further away - you miss the note. Question. Did you know you missed or did you not? If you heard what we did, then practice will fix it, but if you did not hear it then teaching yourself is a problem.
Let's assume you can work out that you can manage (for example) to go from say C to F or G reliably, or from D to G or A, or go a bit higher and do G to D or E, then find songs that do not push that maximum. A good exercise is to do octaves - can you go up and down without missing the note? The more difficult intervals, if we use C as a starting note, are the A, the Bb and the B natural. sitting with a keyboard and practicing until your intervals are really under control means you're ready to perform.
If you sing on stage, your tone, your attitude and what you appear to be count for a lot. I don't mean the sexist stuff, but do you look like a singer - do you stand right, and do you know how to work the microphone, and most importantly can you chat to the audience. If you get them on your side by letting your personality show, they will happily forgive a few mistakes. The old jazz rule - if you play a blatantly wrong note, keep it going and make it a feature and not an accident. Pick your set list that gives you a chance to chat between numbers to kind of recover.
Last thing - you need to be able to hear your voice. In the band we all sing, all the time - 4 separate parts and being able to hear yourself, the music and perhaps the others is absolutely critical. The old folk singers used to put a cupped hand to one ear to try to get the clues - the piano, or the track if you are using them. I once was at a festival where the front of house PA guy had got the bass and the guitar mixed up so my monitor had a rotten twangy guitar in it, somebody else voices and none of me or my bass. I gave up trying to get him to sort it - I'd point at my bass and indicate 'up' and the guitar, not my bass would get louder. The upshot was I played one whole song in E instead of Eb. Ot must have ben horrendous, but I couldn't hear it and thought I'd been spot on. With a monitor with the right amount of me in it, I'd have realised from note 1! What sort of music will be in your set list?
I heard a band recently - the lead singer was the weak link. He could not go low, and he couldn't go high, so he had to wobble about in the limited range he had. His personality though, was really good, and though he was really a poor singer, he got away with it. My voice is accurate, in tune but bland. I am great as a BV singer or doing clever harmonies but my voice is just lacking character I guess!
