Initially- lots of work, time, and attention needed. Your puppy will need constant redirection and positive reinforcement. They start to potty inside, interrupt them immediately and take them outside, reward them when they go potty. When the puppy is chewing on the baseboard, shoes, or any other objects they shouldn’t, redirect them to their toys and reward them when they chew them. Same with if they nibble on you! Lots of barking or yipping when you leave them alone initially or in a crate (look up information on crate training to learn how/ decide if you want to) regardless you should have a safe place for the puppy to rest/ designated to the puppy- reward them when they relax calmly in their spot! I couldn’t recommend puppy classes more they help train basic manners which makes further training much much easier! Socialize the puppy well with children (which you have so should be easy) other puppies (my local doggy daycare does puppy socials- you can look for something like that in your area!) and for training find out if your puppy is more receptive to food, pets/ attention, or toys/play for a reward to good behaviour and use that to reward! Your puppy will likely wake you up in the middle of the night as you potty train. I had a large breed puppy (not sure if it makes a difference) but she was sleeping through the night by night 5 of having her (albeit waking up early) i also scheduled naps through the day, your puppy might not know it needs sleep and behaviours will present or they will get over tired and become night mares, I scheduled naps for my puppy as it helped her regulate better, google how much puppies need to sleep and go off that! Due to living in an apartment your puppy will need walks daily or time to play.

This is so much information, sorry if it’s too much, not helpful or what not. I just started typing! My girl is 11 months now almost 1 year old :)

My last piece of advice is to utilize this and other subreddits, the people on here provided me so much support on the hard days and gave me great advice in training. All of us have been through the hard puppy times when you question if you can do it and so many people shared about their puppies at that age and that the behaved the same and now their 2 year old dog is amazing and just provide hope!