Glad things seem to be sorted out.

If you now have the English version of Firefox you will already have a selection search engines in that including Bing. By default the search bar is located top right next to the bar that you enter addresses into.

If you click the little down arrow and use the "manage search engines" option at the bottom of the drop-down you can move Bing up to the top as the default search engine from that search bar.

If you want Bing for a bookmark or homepage choose by using the listing link

If you have not entirely given up on Google consider adding one or more of the Search engines from this listing http://mycroft.mozdev.org/google-search-plugins.html

(I had initially though you may be in Spain Europe and after English Europe {UK] glancing at your profile I guess that may be a wrong assumption )

Now may also be a good time to consider making backups of the Firefox profile and bookmarks, as I mentioned in an earlier post. You never know when you may need them.

We do not normally do anything special to close threads. The fact that it is now marked as solved will mean most helpers will ignore the thread.