Suggestions:

1. Storing age
Don't have an Age field!  Instead, use a BirthDate (Date/Time) or BirthYear
(Number) field. The age changes all the time, so if you have a few hundred
people, storing the age means your stored data is wrong again almost every
day. You can calculate the age as needed from the birth data. Post a reply
if you need more details of that.

2. Storing gender
If you have a Title field (entries such as Mr/Ms/Dr/Prof/Rev/...), you can
use the AfterUpdate event procedure of this control on your form to have a
guess at the gender and assign a value to your Sex field. This only works
for some titles though.

If you want to do it by looking at the person's name, you would need to
teach it how. That would mean creating a table of common first names, with
the most likely gender to guess. Again, this only works with some names.

3. Name field
Hopefully you don't really have a field called Name. Almost everything in
Access has a Name property, so Access will misunderstand it, e.g. thinking
you are talking about the name of the form instead of the contents of the
text box called Name.

In any case, you really need to break the name down into its parts, which
makes it much more efficient for searching and sorting. Using separate
fields for Surname and FirstName would be minimal.