Formatting a number field

Formatting a number field

I have tried to follow previous posts on this subject, but don't have enough programming skills to make things work.

In short, I have a number field. I want to add "," as a thousands separator. eg  210000000 becomes 210,000,000

If I understand right, I have to create a second field (single line text) and call the input value from the numeric field, then convert it to a string and add the commas.

I've tried everything, but an make this work.

My numeric field is called <non_Comma> and my text field is called <Comma>. Can anybody help me get it working please?