TBF, the shoes and the belt are simpler than you might assume, though there are aspects that you do not want to skimp on with the shoes. For the belt, just be sure to match black or brown to the tone of the suit (and the same with the shoes; belt and shoes should be the same color, traditionally).
The shoes, and this is clutch, should be comfortable and insoles are your friend there, so dropping $20+ on a pair of supportive insoles will save you hours of discomfort if you’re planning on wearing those shoes during the whole workday. Lastly, you can generally find understated-yet-fashionable formal footwear on Alibaba for super cheap — as a stop-gap until you can afford to shop around.
Feel free to reply or DM, I’m happy to help any way I can, neighbor. 🤓🤘🏽