We don’t know what happened to kip and napoleons mom and dad but their grandma leaves them with their uncle and kip is 32(?) and so no one is actually abandoned
Sort-of. Uncle Rico ridicules Napolean and throws meat at him, causing him to fall off his bike and injure himself. He and Napolean later fight briefly although no one is injured.
A cow is shot by a farmer off screen. Specifically it shows the farmer cocking a gun and as soon as that happens Napoleons bus drives in the way of seeing the cow getting shot. Then you hear a gun shot and all of the kids in the bus start screaming.
Tina the llama is verbally abused and also fed human table scraps, including ham. Llamas are strictly herbivorous so this implies that the family either doesn't know how to care for the animal or doesn't really feel bothered about it (likely the second, due to the verbal abuse). Either way, it constitutes neglect as she is not being fed appropriately.
A woman has saucepans put over her boobs by uncle rico, he doesn't ask before doing this. He also hits on minors as mentioned before and is just creepy in general, but there's no rape, graphic assault or harrasment, etc.
people are put in headlocks multiple times, usually by the bully characters. people may be choked a few times otherwise but i don’t remember it that well.
Uncle Rico gives breast-enhancement ads to Summer, Trisha and Deb who are all underage; also encourages them to call him if they need said enhancements
In a blink and you'll miss it moment after throwing meat at napoleon, uncle Rico spits out the steak he was eating into his hand and puts it back on the plate. (The actor was vegetarian at the time)
it is unknown whether napolean has autism, but his mannerisms and behaviour certainly mimic those of neurodivergant people. He is bullied by uncle Rico and his peers because of these mannerisms.
Tina (a llama) is called fat, and another joke towards debbie, who is seen drinking low fat milk, Napoleon goes up to her and says "Do you drink that cos you think youre fat? cos your not really, you could drink whole milk if you wanted to." so not really anything extremely hateful, just some mildly fatphobic jokes.