indent first line in paragraphs

Microsoft Office Word Docmanagement

I have finished my text and I found out that I have to indent the first line 
of every paragraph. It seems that if it is a new document and I am typing a 
new paragraph, I can still set the parameters of the indentation. But now 
that the text is finished, it's hard to do it. Do you have an idea how to do 
Are you using Outline Styles or is it Normal style?