Excel

Excel

Removing the .jpg in 3 cells then concat them

=LEFT(A1,LEN(A1)-4)&","& LEFT(B1,LEN(B1)-4)& ","&LEFT(C1,LEN(C1)-4)

• Results

one.jpg

two.jpg

three.jpg

one, two, three

Suppressing errors if you have a blank line

=IFERROR(LEFT(A1,LEN(A1)-4),"")&","&IFERROR(LEFT(B1,LEN(B1)-4),"")& ","&IFERROR(LEFT(C1,LEN(C1)-4),"")

Create a sequence of 20 rows

= "NO." & SEQUENCE(20)