There are three different ways you can set up your website if you have content in multiple languages.
One site, one post.
When you write a post, do the first half in one language, then, at the bottom of the post, write it in the other language. Anyone reading your site just knows it needs to scroll. You can also add a page jump so your readers can skip ahead to their language.
One site, two posts.
You can have one site with different posts and pages with the same content in different languages. When you write a post, write it in one language, then create a new post and write it in a second language. You can add categories to your posts to organize them. You can also have a link on each post or page to send people to the same content in the other language. Then, create a menu to link to your other language. You can use custom menus to make it easier for your readers to find all the posts in each language. Create or edit a custom menu or add an element to your menu linking to your category for your other language.
Two sites, two posts.
Create two sites using the same theme. You can use two different domains names or set up a subdomain of the main domain. You can use custom menus to crosslink your sites. Add a custom link to each menu that links to your other site so visitors can switch to a language easily. Set one site’s language to the first language in which you write and the other to the second language. Each time you write a post, write it twice. Once in language number one in site number one, and again in language two on site number two. Your followers can subscribe to one site or both, and your post will appear in the tag section in the Reader for each site’s language.
To start your website, you just need to create your WordPress account here: https://wordpress.com