Hi Jordi Cido,
First of all, a warm welcome to CodeRanch!
Jordi Cido wrote:What tool do you recommend in order to practice with mock exams?
In the
OcajpFaq (besides other very useful information) and
this thread you'll find an overview of all available (free and commercial) resources (study guides, mock exams, video courses,...) to thorougly prepare yourself for the certification exam. And on the
OcajpWallOfFame you'll find plenty of (links to) experiences from other ranchers (including resources they have used). So it can be useful to determine which resources are useful (and which are not).
Hope it helps!
Kind regards,
Roel