Why do you want to learn Excel? Is it a requirement for a new job, or do you hope to set up a personal budget, or some other reason?
If it's for work, or a new job, and you need to learn quickly, then it might be best to go to a half day or full day course, where an instructor can answer your questions, and provided a structured course that covers the basics.
If it's for home, and there's no rush, then think about how you learn other things. Do you like to read, and follow written instructions? If so, browse through the Excel books at your local bookstore, to find one that appeals to you.
There are also online written tutorials, like the ones I have on my Contextures.com website, and on some of my Hub Pages. There are many other Excel tutorial sites, and Google will help you find them.
if you prefer to watch something, and then try it for yourself, check out some Excel videos. My site also has Excel video tutorials, and many people have posted tutorials on YouTube,