Jquery to javascript - amend slider position to start on 2


I want to make the second slide appear in the middle on page load and have slides 1 and 3 either side (so we can see a teaser either side).

I found this code below but it is Jquery and I am not sure how to translate to javascript. Please can someone help?

All the rest of my custom code is in vanilla javascript and so I am guessing you can’t mix and match as when I did, it didn’t work anyway.

Should I put this code at the top of my custom code because because it is on page load?

$(document).ready(function() {
$(‘#gal1 div:nth-child(10)’).trigger(‘tap’);

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