Do organisms intentionally mutate

Yes

Explanation:

So, yes, we can end up with genes we wish to have in an organism ... Well, the problem is that a mutation is actually either a deletion or insertion within a sequence of nucleotides, things that make up a gene. Now, in later generations of offspring, genes will mutate randomly on their own anyway.

No

Explanation:

Mutation is basically a glitch in you DNA. It can be brought upon an organism by environmental factors like radiation, but an organism can't choose to mutate.