Sounds within the range of normal for a 19 month old to me!
It's a difficult age, because they are starting to do things you know you need to nip in the bud, but often they just don't understand when you try. DS is 18 months old and we have similar issues. I will quickly go through what I do.
I tend to just ignore, but carry on with what I was doing. For example he lay down in the street the other day screaming because he didn't want to hold hands, so I picked him up instead and carried him (horizontally! ) to the park where we were going. I could have cancelled the park trip, but I thought that at that time, he was frustrated because he wanted to run around, so the park was probably the best place for him to be. And they don't tend to connect events, like "If I have a tantrum we will go home" yet anyway.
Usually I just move away from him or move him away from the person. If he has hurt someone then I say sorry to them "for" him (he can't say sorry yet) and hopefully as he gets older he will apologise himself. If he is hitting I can usually grab his hand before he makes contact and just say "Too rough!" and show him a nice way to stroke someone (or whatever) then when he is gentle, I say "That's right, gentle, good boy" and after a while, once I was sure he knew what gentle meant I started telling him to be gentle when he was being rough. You have to make sure they know what you mean though, otherwise you say "be gentle" every time they hit and they start to think that "gentle" means hitting! I also tend to overreact if he hurts me - especially with hair pulling, which sometimes makes him laugh and sometimes makes him look a bit worried, and he will give me a cuddle.
I say "No throwing toys, that is too rough. You can throw this ball." and find something soft that he can throw, away from people. This works surprisingly well! To the extent that I will say "No", and he will throw the forbidden thing to the floor, then himself, but then get up and throw the ball around quite happily. It took a few attempts and lots of confiscated toys to get to this point, but if he throws/hits more than once then I automatically take the toy away.
Once he had a particularly memorable, very overtired tantrum and threw everything I gave him, I was getting frustrated and wanting to throw things myself, so I strapped him into his pushchair (so I could get out of the way!) and gave him a toy and said "Show me how angry you are!" and he threw it as hard as he could across the room. I said "Wow, you are so angry!" and gave it back, he repeated this a couple of times, and then he laughed, started throwing it less hard, and eventually calmed down and accepted a cup of water. He was only about 16 months at this time and had no words, so I didn't expect him to understand at all but it really seemed to help. It's just about teaching them to manage their anger in a controlled, safe way.
I still can't give DS a whole meal in one go, I tend to give him very small portions, or he gets overwhelmed. So I will offer him a forkful each of 2-3 things from his plate, whatever he eats I will then give him more of, if he doesn't eat, then I just move on, either give him a fromage frais if I need him to eat now, or just give up on eating for the moment and try again in about an hour or so. He has never eaten very much so I think I have stopped stressing about it so much!
- Telling off/going straight back to things
I think this is just part of this age group - it's just something you have to ride out, I am afraid. When he keeps going back to things, I find it easier to restrict access to the things in the first place, e.g. there is a vent on the wall where the fireplace originally was in my house, he pulls at it, so I have hidden it with a large box for now, which doesn't look great, but I am hoping to get a chair or something to go there instead. He also tries to turn the cooker knobs, so I don't let him in the kitchen unsupervised, which is a pain but necessary until he is older and can understand more.
HTH