Once you have found that water is seeping out from under your toilet, there are only 2 things that could be the cause of this.
It will be either a cracked toilet bowl or a bad or misaligned toilet wax ring.
The task to replace your toilet wax ring is a very simple process under normal circumstances. However there are times when the toilet mounting bolts decide they do not wish to come loose. This can be caused by corrosion or the flange that they are attached to is rotted or damaged. This will require some extra effort to get the bolts and toilet removed and may require the flange to be replaced.
Under normal conditions, this project should take about 15 minutes to complete. You will need just a few basic tools such as pliers and a socket or adjustable wrench.
Using No Wax Toilet Ring will help prevent future leak issues with your toilet.
This short video from FIX IT Home Improvement Channel is a great guide to help you with this project.
