<p>No one will care about your age. Gap years are becoming more frequent as long as you use your time productively - working, volunteering, involved in a project, etc.
However, if you were enrolled in a college (vs. trade school, community education program, apprenticeship, postgraduate year in a secondary school, further ALevels…) you would be considered a transfer.
Transfers to Top 25 universities are few and far between (rare) and almost all are “lateral” transfers, ie., coming from a school in the US, often a Top50 or Top100 4-year university. Some universities, such as USC (CA) or Cornell, take a lot of transfers, but transfers from community colleges with which they have agreements.</p>