If you are at all concerned about project management then I'd recommend you don't use Excel. It's designed for fixed column spreadsheets ie things can't move about on the page. You'd be better of with Microsoft Project or a cheaper version eg Turboproject. These offer movable Gantt views.
In general each project is different so templates usually aren't very helpful. It's better to get used to thinking in terms of a Work Breakdown Structure. Think of all the things you need to deliver, what needs to be delivered in order to deliver them, and so on. Then build your plan around this pattern, adding the tasks that you need for each deliverable, its duration, who's going to do it and what dependencies there are between of all this.
The key to successful project management is not process or tools any more than fancy paint and canvas determined the quality of the works of Van Gogh.