write an Apex test class that pass 85% or above

as described
this is the class

public with sharing class dam_DigitalAssetOperateController {
@AuraEnabled(cacheable=false)
public static void updateAssetAndSectionItem(String assetApiName, String descriptionApiName, String itemId, String description){
Section_Item__c secItem = [SELECT Id,Asset_Item_ID__c,Section_Name__c,Description__c FROM Section_Item__c WHERE Id=:itemId][0];
String queryStr = 'SELECT Id,'+ descriptionApiName + ' From '+assetApiName+' Where id = \''+secItem.Asset_Item_ID__c+'\'';
system.debug(queryStr);
sObject assetItem = Database.query(queryStr)[0];
system.debug(assetItem);
assetItem.put(descriptionApiName,description);
secItem.Description__c = description;
update assetItem;
update secItem;
}
}