Redirect - these behaviours are all normal and discipline will have no effect. I just say " we don't do x" or "gentle hands" and then remove her from the scenario. If throwing food, I remove food. If hitting, I put her down or move her somewhere safe and then distance myself. At this age they aren't even testing boundaries - they aren't even aware boundaries exist. They are literally just illogical chaotic beings with poor impulse control.
Don’t think of it as them doing something ‘wrong’ as such. They are developing/exploring and all part of it. Redirect but also rather than focusing on the no statements, say what you want them to do. So when we had food dropping, we got a second plate and said to put it there. She likes to draw with pencils but will also sometimes want to run around with them so again rather than focus on the no, I’ll say pencils are for paper only. And then hold boundaries so if she’s not listening or following or repeats then I’d take away the food or pencils. Not in a you didn’t listen way or anything like that but in a this is over now. She might get upset and I’ll give her comfort to process the feeling and don’t say things like well if you hadn’t done x. Then we move on. I read somewhere that little ones sometimes don’t hear the no in sentences. So if you say no we don’t throw food, they may just hear throw food or want your reaction.
Apparently you can test their understanding by holding two objects they know like a banana and apple and say which is NOT the apple, they are likely to just hear apple and go for that. So until they can really understand the not/no in things, better to focus on telling them what to do and redirect and just keep consistent/repetitive with it. Of course you can still use no/stop and more effective as one word statement and saved for things when it’s really needed so the impact is there, usually involving safety things.
Rather than saying what not to do say what to do ie walk instead of dont run. Theyre likely just to hear run and not the dont. Ive started getting her to say 'bye bye' to food when finished. If she throws it on thr floor i pick it up put it on the tray and hold out het hand to give me it and say bye bye then i put it in the bin. She's now started to give me the plate and says all gone / bye bye. Its taken a while and consistency. For hitting i use 'ah ah' and shake my finger (i use it for anything i dont want her to do) she recognises that now.
Redirect mostly. I give her a bowl and tell her to put food she doesn't want in that. I redirect her to hit something she can hit (we have a ball on a bouncy cord that's fun to smack). This mostly works for us but if she does continue to throw food, she's taken away from the highchair. If she continues to hit, I would tell her mama doesn't want to be hit and I'm moving away so my body can be safe, and then I'd move away.