Image at the top of the page + margins

Question

I am trying to do my company paper. After few tries I finally put my image at the top of the page. But after that when I am using \usepackage{scrextend} and trying to change margins, the text is above my picture. Can anyone help me?

And one more question: can I put some text ON the image? For example 3 lines, white font on the left side?

\documentclass[a4paper,11pt]{article}
\usepackage{polski}
\usepackage[cp1250]{inputenc}
\usepackage{graphicx}
\usepackage{wrapfig}
\usepackage[left=0.01cm, right=0.1cm, top=0.01cm]{geometry}
\pagestyle {empty}
\usepackage{scrextend} 

\begin{document}
\begin{wrapfigure}{L}{0.1\textwidth} 

\vspace{-18pt}
\begin{center}
\includegraphics{PAPIERfirmowygora.jpg}
\end{center}
\end{wrapfigure}

\begin{addmargin}[2cm]{2cm}
Some text.
\end{addmargin}

\end{document}

The link to the image:

Answer 1

To get the image at the top of your pager you should get rid of your used environment wrapfigure. Use instead only \includegraphics like this:

\vspace{-18pt}
\noindent\includegraphics[width=\paperwidth]{PAPIERfirmowygora.jpg} % <============

The \vspace is used to move the image at the top of the page and \noindent is needed to get no white space at the beginning of the image.

To get white text on the left of the image you can use package textpos:

\usepackage[absolute,overlay]{textpos}

Then you can use the following code to add the white text (remember to call package xcolor to get color white be defined):

\begin{textblock*}{12cm}(5mm,5mm) % <===================================
  \color{white}\noindent
  Text in first line \\
  Text in second line \\
  Text in third line
\end{textblock*} % <====================================================

With the complete code

\documentclass[a4paper,11pt]{article}

\usepackage{polski}
\usepackage[cp1250]{inputenc}
\usepackage{xcolor} % <=================================================
\usepackage{graphicx}
\usepackage{wrapfig}
\usepackage[left=0.01cm, right=0.1cm, top=0.01cm]{geometry}
\pagestyle {empty}
\usepackage{scrextend}

\usepackage[absolute,overlay]{textpos} % <==============================
\usepackage{blindtext} % <==============================================


\begin{document}

\vspace{-18pt}
\noindent\includegraphics[width=\paperwidth]{PAPIERfirmowygora.jpg} % <============

\begin{textblock*}{12cm}(5mm,5mm) % <===================================
  \color{white}\noindent
  Text in first line \\
  Text in second line \\
  Text in third line
\end{textblock*} % <====================================================

\begin{addmargin}[2cm]{2cm}
Some text.
\blindtext
\end{addmargin}

\end{document}

you get the result: