Hello,
You can do it using a variable, something like this:
var dateExample = new Date("2019-01-02");
$w.onReady(() => {
$w("#dataset1").onReady(() => {
$w("#dataset1").setFieldValue("timeField", dateExample);
});
});
Where:
#dataset1 - ID of the dataset in question, that you can find in the Properties Panel (Velo: Working with the Properties & Events Panel | Help Center | Wix.com)
timeField - Field key of the relevant field.