Yes, you can create a simple portfolio on Carrd. There is even an entire template category dedicated to portfolios. Choosing this kind of template will allow you to create your one-page portfolio much more quickly, and you can be sure that it will look good. However, if you decide to expand your portfolio, you will probably want to start looking for another website builder that will let you control your site in more detail or maybe even allow you to start blogging and selling your work online.