JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent border">
  <div class="fixed-component border">
      Fixed Component
  </div>
  <div class="flexible-component border">
    flexible component
  </div>
</div>

CSS

.parent {
  height: 100px;
  display: flex;
}

.flexible-component {
  flex: 1;
}

.fixed-component {
  width: 100px;
}
.border {
  border: 1px solid black;
}