How can I convert large set of text to number

[Edidex]

Please how can I change a large set of text into numbers without affecting the already existing set of number in the column.

 

[vletm]

Select that range
Data > Text To Columns...
do selections

 

[Belleke]

What use is a picture that no one can read?
More, what does a picture in a Excelforum?
This is not a photoshop forum.