Range: collapse() method

The Range.collapse() method collapses the Range to one of its boundary points.

A collapsed Range is empty, containing no content, specifying a single-point in a DOM tree. To determine if a Range is already collapsed, see the Range.collapsed property.

collapse()
collapse(toStart)

const range = document.createRange();

const referenceNode = document.getElementsByTagName("div").item(0);
range.selectNode(referenceNode);
range.collapse(true);