What would you style this shirt with?

[marmiteisgod]

I'm 23, and the size of a bus on the larger side.

I thought jeans but not sure if it's a bit casual?

(Also if the shirt is not good, those opinions also welcome)

Sorry I mean to say formal, as in the shirt is a bit boxy for jeans?

I'd wear either pink or grey chinos or a white midi skirt in an A line or pleated style.
No to jeans with this shirt unless they're white, grey or pink.