You might want a list - or maybe not, depending on the meaning of the content. I appreciate that you are trying to use less elements and instead a pseudo element, but consider a custom-element as a way to 'not use' an unsemantic 'div' or something - and win in both ways.
<ul class="thing-list">
  <li class="thing">
    <circle-component>
      <span>Text in circle</span>
    </circle-component>
  </li>
  
  <li class="thing">
    <circle-component>
      <span>Longer text in circle</span>
    </circle-component>
  </li>
  
  <li class="thing">
    <circle-component>
      <span>Longer text in circle</span>
    </circle-component>
  </li>
  
  <li class="thing">
    <circle-component>
      <span>Longer text in circle</span>
    </circle-component>
  </li>
</ul>
From there - there are many ways to do this. You could use the height: 0; padding-bottom: 50%; type trick, but it might cause you more trouble than being squishy is worth in this case.
Here is the setup for using flex-box / and also a grid alternative. Don't be afraid to use custom-elements! They are easy to read - and well, it's 2020! : )
I'm sure that Bulma has some neat conventions, but in this case I see no reason to use any framework. CSS in 2020 provides us a really lovely set of options.
/* reset + project setup */
* {
  box-sizing: border-box; /* look this up if you don't already use it https://www.paulirish.com/2012/box-sizing-border-box-ftw/ */
}
/* components FIRST */
circle-component {
  display: block; /* custom components are inline by default */
  width: 120px;
  /* one of the few places I would EVER set an explicit height or width */
  height: 120px; 
  border-radius: 50%;
  border: 1px solid red;
  display: flex;
  flex-direction: column; /* one way to do that... (center) */
  align-items: center;
  justify-content: center;
  padding: 10px;
  text-align: center;
}
/* then... context */
.thing-list {
  display: flex; /* flex version */
  flex-direction: row;
  flex-wrap: wrap; /* let it break to the next line */
}
.thing-list.grid-version {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); /* depends on what you want to happen */
  border: 1px solid blue;
}
.thing-list .thing {
  padding: 10px; /* maybe */
}
/* you could totally use position absolute for the text if you want - but it's nice to not need that - and let the text flow naturally */
fiddle: https://jsfiddle.net/sheriffderek/Lbjcw8gp/
A few thoughts on flex-box patterns to help solidify them:
Almost all of the UI layout comes down to just this