Choosing the right SSL certificate depends on your situation. In short, you have two options.
Or you are a private person and mostly want a secure website. In that case, all you need is an SSL certificate with domain validation.
Are you a company or a commercial activity? Then you should choose an SSL certificate with extended validation. Your company information will then be included in your SSL certificate. This will allow visitors to learn all about the company behind the website, which will instill more trust and increase your sales.