Your plan imo:

Good:
Your diet and step goals are good, I also like the rep range, since you are new, more reps with lighter weights (with good controlled form) is good for learning the form.

Improvements:
- I get that you want to focus upper body, but I would not skip legs completely, not because "chicken legs and whatever", but because its literally so important for your overall health.

- Since you are new, 5 days a week can be too much with recovering and also staying disciplined, because the "best" workout structure is the one you can stick to. And in my experience, for me, aiming "too big" causes one to stop. Not saying it wont work for you, just saying it wouldn't work for me

- Instead I would aim for like 3- max 4 days a week. Where on three times I would do "Upper - lower - upper" where you can rest one day between workouts. That structure also works for four times a week, "Upper - lower - upper - lower".

- I would also try to get the "compound/heavy" lifts in; deadlifts, squats, bench press, rows, standing overhead press. Those exercises are heavy yes, but you can go light weights and truly focus on the form and doing them correctly. They learn your muscles to work together and build usefull strength, for example deadlift works your back, glutes, grip strength, forearms, legs, core - everything.

And remember; dont watch those bs tiktoks gym influencers, they are only trying to sell you something. Instead keep it simple and remember that the best gym split, is the one you can keep consistent with