It is not very likely that you will become a CEO’s secretary right off the bat, no matter what you do - it is more likely that you will be the secretary for a VP or Director, who is then promoted to executive VP and eventually selected to be CEO.
If your goal is to be on the admin side of things and work as a secretary or administrative assistant, then a bachelor’s degree may not make sense unless finance is not an issue. There are associate’s degrees and/or certificates that can prepare you for those types of roles and may prove just as useful as a bachelor’s degree but without the high price tag of a four-year university. I’d look more broadly than bachelor’s degrees.
With an accounting degree, secretarial/administrative work would generally be considered underemployment, since you would be qualified to work in higher-level roles as soon as you graduate (think of it like a lawyer working as a paralegal or an electrical engineer working as an electrician). Underemployment isn’t a bad thing if you want to be doing that work, but it just means that you can achieve the same goals without as much post-secondary education.