Like Hood values
1-Rare
2-Unlikely
3-Possible
4-Likely
5-Certain
Impact value
1-Insignificant
2-Minor
3-Moderate
4-Major
5-castrotrophic
The Score column is multiplying Both Like hood and Impact and giving me final score but I need to add text of
“Very Low” to value range of 1-5--------Filled colour Green
“Low” to value range of 6-11------------Filled colour Yellow
“Moderate” to value range of 12-16------Filled colour Amber or Orange
“High” to value range of 17-20 -------------Filled colour Red
The table is as shown below

Thanks in advance
OK, you can use this code as the custom calculation script of your score field:
var score = Number(this.getField("Dropdown1").valueAsString) * Number(this.getField("Dropdown2").valueAsString);
if (score==0) {
event.value = "";
event.taret.fillColor = color.transparent;
} else if (score<=5) {
event.value = score + " : Very Low";
event.taret.fillColor = color.green;
} else if (score<=11) {
event.value = score + " : Low";
event.taret.fillColor = color.yellow;
} else if (score<=16) {
event.value = score + " : Moderate";
event.taret.fillColor = ["RGB", 1, 0.64, 0];
} else if (score<=20) {
event.value = score + " : High";
event.taret.fillColor = color.red;
}