This tutorial will introduce you to the several methods of stochastic process. I assume you have learned basic statistics and have some knowledge about probability distributions.
What is Random Walk?
Random Walk from Normal Distribution
Simulation of Random Walk in Microsoft Excel
How to forecast using Random Walk?
How to know the probability distribution of a random walk?
Resources on Stochastic Process
Preferable reference for this tutorial is
Teknomo, Kardi. (2017) Stochastic Process Tutorial .