<select id="year"></select>
for (let year = 1920; year <= 2020; year++) {
let options = document.createElement("OPTION");
document.getElementById("year").appendChild(options).innerHTML = year;
}
<select id="year"><br>
<option value="">year</option>
<script>
let y = 1969
while(y<2025)
{
y++
document.getElementById('year').innerHTML += '<option>'+y+'</option>'
}
</script>
</select>