Error while training the machine

When I’m trying to train the machine it is showing an error :could not convert string to float .
Our data set contains the following fields area(string) and cost of production (integer and float),crop(string),M.S.P(float).
It is not taking string as an input for the training sets.
Give us suggestions regarding how to give the string as input for training the machine.

machine training file
training data set


If you use keras, there is a class ( that can form a one-hot vector matrix.
Here’s the link for a similar question, try it out.