Layout

Many pages are designed by rows and columns today. There are basically three different methods to create multicolumn layouts.

Float

Flexbox

Grid

Float existed before Flexbox and Grid. It is still in use, but not that much anymore. Flexbox is more flexible. It positions elements based on one axis (horizontal or vertical). If you need both axes, probably better work with Grid.

Frameworks

Instead of working directly with this CSS properties it’s convenient to work with CSS frameworks which are built on top of these properties, like:

Flexbox Grid

W3.CSS

Bootstrap

Using these frameworks often reduces the amount of work but likely also the individuality of your page.