My boat shakes bad at low speeds but is fine when i get up to top speed.My prop is in pretty bad shape could this be why?

Could be idling rough from dirty carbs. When you say slow, do you mean no wake?

What is the boat and motor make and model?

There is a wake but small the engine is a 1989 evinrude 48hp spl

If your prop is badly damaged and therefore out of balance it could be shaking and worse it could be beating up your lower unit bearings.

go get your prop repaired and make sure its not cupping the water(i dont know what word to use) like make sure its not making huge air bubbles down by the prop.  if it is then def get that prop repaired.

Get your carb cleaned.  Your prop has to be badly damaged to shake the motor.

go get your prop repaired and make sure its not cupping the water(i dont know what word to use) like make sure its not making huge air bubbles down by the prop. if it is then def get that prop repaired.

The word you are looking for is "cavitation."