Add Text in new line in all the .txt files in the folder [closed]

Can anyone help me get this done. I need to create a batch file, that will add specific text in start/beginning of the file content,

like if my txt file content start from first line

bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla
bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla

I want to insert “hello” in the first line.

hello
bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla
bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla

Thanks I searched a lot but couldn’t find a correct solution hope you guys can help.