i would suggest you take the time and learn how to do it yourself, html is quite easy and thats all that is required for creating a basic portfolio. add a few simple images from any type of image editing software, and you have yourself a site.
the sites that were listed above are good, so if you feel like going that route then you should have no problem, but a quick google search and a few hours of your time will lead to a much better understanding of simple coding and design, and it will never hurt to have the experience.
<a href="location of your art page">art</a>
<img src="location of image file on server">
Here's where my text content will go
theres a fully functional html site, done in roughly 3 minutes. if you feel confused or have questions, feel free to give me a shout over private message or any of my messaging platforms (you can find my info in my profile). best of luck