Carrying on with the example of a coffee shop, a business plan consultant will figure out what the best location would be. They already know coffee shops do well in areas with a certain demographic in place. These include students and workers, who are within close proximity to book stores.
You must know what a website template is. A website design template is nothing but an already designed websites in which you can easily amend any changes related to the content, according to your requirement.
Besides, your friends may be 100% behind you in your new venture, but, in case you are hoping to involve others who have actual money to invest, you may need to be able to make a convincing case. Wouldn't it be nice to have anticipated possible questions and be ready with plausible answers? If you are risking your own money, that is perhaps even a stronger reason to do some indispensable planning.
So, rather than looking around for an existing plan and then designing your own plan along the same lines, it would be a better idea to use software that allows you to create your own template.