There have been quite a few questions on this topic on various web forums, including here on Biostars - can you search, please? It is a skill in its own right to be able to seek out information, process and interpret it, filter out 'noise' / 'jargon', and then make inferences from it. Also, what happened to your idea, here - Cancer exome sequences ? - it seemed like a good training exercise for you.
You graduated in Biotechnology but want to be a bioinformatician or just 'add on' bioinformatics skills to your CV? Why did you choose to study biotechnology?
I've been looking for an internship for the same but I didn't get any.
How hard did you try? - please elaborate. it can take time to find the right position.