How do I convert a virtual column value to an array with Number datatype

[AttendX_officia]

I have attached the image of my data.
All the columns to the right of Column Name[Total Lectures] are virtual columns .
The rest are containing app formulas or expressions. I need Column[No. Lectures Absent] to return all the values of column names starting with the word “select” with datatype Number.
I need [No. Lectures Absent] to be
0
1
0
2
0
0