This is how you can get the url of a field link rendered as a string (internal or external).
<a href="{{ node.field_link.get(0).getUrl().toString() }}">{{ node.field_link.get(0).title }}</a>
This is how you can get the url of a field link rendered as a string (internal or external).
<a href="{{ node.field_link.get(0).getUrl().toString() }}">{{ node.field_link.get(0).title }}</a>