Is it ok to apply for more than one Phd student program? [duplicate]

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• Is it advisable to apply to more than one PhD program? 1 answer

I am really into going to PhD next year. I found some programmes that suits me, but I am asking myself, if I should apply on more programmes than one.

The problem is, that I have a weak background in researching, so there exists option to be rejected.

So here comes the question: Should I apply on more PhD programmes?

Some programmes require reference letter from professors of supervisors. Should I ask for genereic reference letter?

Thanks in advance for answers.