Google Sheets Function: SPLIT
The SPLIT function divides text based on a defined delimiter and places each fragment into a separate cell in the row.
Usage:
=SPLIT(text, delimiter)
or
=SPLIT(text, delimiter, split_by_each, remove_empty_text)
Example of Use
The goal here is to use a single SPLIT function per row to complete each column of the table:

Enter in the SPLIT function:
- text: the data to be divided
- delimiter: the delimiter(s)
- split_by_each: 1 (default) = each character in the delimiter will be considered a separate delimiter (for example, entering "/-", the text will be divided at "/" and "-"), 0 = the delimiter remains whole (for example, entering "/-", the text will be divided only at "/-")
- remove_empty_text: 1 (default) = empty fragments are removed, 0 = empty fragments are kept
The formula here is:
=SPLIT(A2,"/")

This formula is equivalent to:
=SPLIT(A2,"/",1,1)
Retrieve a Single Value
The SPLIT function returns an array of values, and the INDEX function returns one of the values from an array. Therefore, combining these two functions allows for returning a single fragment from SPLIT.
To return only the age (at column 3 of the table), enter:
=INDEX(SPLIT(A2,"/"),1,3)

If needed, you can copy the Google Sheets document (or view the document) with these examples.