how to change language
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  I realize that all the (working) pages are called with "/?q=node/somthing" instead of "/node/something"


To make your path aliases be human readable, pls check if Path module is enabled and then go to Administration » Configuration » Search and metadata  » Clean URLs and check "Enable clean URLs" checkbox. If it is not editable, you should ensure that PHP Rewrite mod is enabled.

To have your content displayed in diffrerent languages correctly you need:
1) Have Locale and Content transpation modules enabled. Both of them are Core modules.
2) Goto Home » Administration » Configuration » Regional and language » Languages and add the languages you need. Ensure that all required langs have ENABLE checkbox chacked. Also ensure that you have the correct Path prefix language codes (can change is edit Language) for each lanf, like "en" (without quotes) for English, "fr" for French etc.
3) Goto Administration » Structure » Content types » Your_content_type (that one you're using for creatinf translatable content) and ensure that in *Publishing options" tab "Multilingual support" is set for "Enabled, with translation".
4) Now create your piece of content and in creating content form set Language select box as "English" and set the URL alias as "policy-1" for example. Save it. Now you should see a "Translate" tab (near View/Edit tabs). Press it, select the lang you need and follow add translation link.

Tip: I don't know how your theme looks, so i'm not sure if you have a lang switcher for users or lang links displayed when viewing transled content. But if you use the same alias for all your translation, you can easily check if it works or not. For example if you set "policy-test" as Path alias for all transleted versions of your test node, you should be able to visit it via [yoursite]/[lang-prefix]/policy-test, i.e. via [yoursite]/en/policy-test or [yoursite]/fr/policy-test etc.

P.S. you don't need to use your lang prefix in path aliases for any language. Drupal will do it itself.