Hi,
microchip has application notes about the use of timer/counters and frequency generation.
There are a lot forum threads.
There are internet tutorials, example code, even videos.
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Show what documents/informations you refer to.
Show what your idea is, your calculations, your code.
Tell us what you expected and what you see instead.
Ask elaborated (and not global "can anybody help") questions.
In short: show your effort ... and there will be many people here to help you.
Klaus