The most common test of cognitive function which is given as a screening test to people who are older or have suffered a neurological insult is the Montreal Cognitive Assessment. It is absolutely not an intelligence test. Rather it is a screening test with a cutoff defining normal vs do further evaluation. So a low score means you need more evaluation and a normal score means you do not have evidence of dementia as measured by this test. A high score means you do not have evidence of dementia. It does not mean in any way that you are smart.
For fun you can take the test online. It is not the same as having it administered in a clinical situation so do not take a passing score as meaning you have no concerns. Nor should you take a failing score as proof of a problem. But I thought many might wish to see what the test entails.
Montreal Cognitive Assessment (MoCA): Administration and Scoring - YouTube has some instructions
The Montreal Cognitive Assessment (MOCA) - YouTube shows the test being given