Well, in general, you shouldn't go out of your way to feed your pup any human food. Dogs metabolise their food differently so what might be great for humans may be toxic to dogs. But still, your dog can eat a number of human foods safely. Things like white rice, carrots, banana, etc are fine for your dog, but again, always remember to feed them these meals in moderation. For a more comprehensive list of safe human foods, you can check out this blog post:
https://dulhamvetclinic.com/the-pet-friendly-food-meter-for-dogs/

I get why you're iffy about getting a pet because of your busy work schedule but all I can say is, you can. Pets have different temperaments; there are some that are very clingy and might not be okay being left alone for long hours, but there are also some who are independent and don't mind having their owner away from them most of the time. You can adopt a pet like that. The only thing I'll advise is that before you leave your pet at home, you should 'puppy proof' your home. Meaning, make your house safe for your pet since you can't be there 24/7 to monitor them. You can read more about 'puppy proofing' your home here:
https://dulhamvetclinic.com/puppy-care-10-tips-to-puppy-proof-your-home/
Goodluck with your pet!

Thankfully, there are a good number of pet boarding facilities in Nigeria today.
You can check this blog post out for a comprehensive list of them: https://dulhamvetclinic.com/7-recommended-pet-boarding-facilities-in-nigeria/

Firstly, your puppy is extremely cute.
Secondly, I saw the update post about which human soap is good to use to bath her and nooooo, please don't do that. Never do that. Human products are way too harsh for dogs in general so it's better to just avoid them totally. Wait another day to bath your puppy with dog shampoo. I read all this from a blog post by a vet clinic:
https://dulhamvetclinic.com/a-complete-guide-on-puppy-care-for-first-time-owners/

Dulham Veterinary Services. Veterinary clinic, emergency services, pet boarding, pet food and supplies, pet sales and a resource of pet care tips.

Addresses: 19 Chief Yesufu Abiodun Oniru Street Victoria Island - Lagos.
42 Olokonla Turning Point by Road Safety Office, Sangotedo, Lagos.

Phone Number: 0808 048 1445 or 0806 632 9826.

Website: https://dulhamvetclinic.com

Hmm. Well, as a first-time owner of a dog, taking care of a puppy can be hard. They're like little, fast, mobile babies; they need care and love, and they like to be swaddled and cuddled with affection and attention. So please, do refrain from beating the puppy; he/she doesn't know any better and beating him/her will only lead to them developing some sort of negative trait (like being overly fearful or anxious whenever you come close) that will affect them even as a full grown dog. Rather, potty train your puppy: create a schedule for them to follow. Feed them at certain times, and wait about two-three hours and take them out to a designated spot for them to relieve themselves. This will make it much easier for you to track their poop-times and for them to know the right place(s) to run to when they need to do their bathroom business.
You can check out this article for more information: https://dulhamvetclinic.com/a-complete-guide-on-puppy-care-for-first-time-owners/

Puppies are very different from cats but I have a feeling your puppy will grow on you, haha. Wishing you the very best of luck!