It's true for custom-designed sites which are usually made for big business. Such sites usually have very cool and unique design, many interesting and convinient functions and so on, that's why making them takes much time and is really an expensive thing. But for such case as yours there are many methods of making a totally free site with a good quality
First of all you should register domain name for it. Then your main things will be content, design and site's functions, for all of these you'll need a special web building platform. There are really many of them but for such newbie as you I really recommend Wordpress, it's a free one and very easy for using even for total beginners, you'll need only some basic tech skills for working with it
And in case of design just use web templates, with them building of your site won't take no more than several days. For example, photography portfolio wordpress theme
https://www.templatemonster.com/category/design-photography-wordpress-themes/ is rather popular and simple to find, in case of templates you'll get ready site models which you can easy change according to your needs. That's why they're a very good choice for newbies too, besides they're usually cheap or even free so in this case you won't need a great budget.
But I should mention that free ones rather often have limits for some functions, design and upgrades so decide firstly which certain ones you need before choosing them.
Good luck!
