Supposedly, you can use a Wildcard for the Select item activity.
So in the Item property, you would place the string like this: "*"+variable+"*"
If the wildcard doesn’t work though, you can also get all the items in the dropdown using a Get Attribute activity, using items as the attribute. I have used this method in the past. So, essentially, you get the items stored in an array variable from the Get Attribute activity. Then find or filter it based on your variable.
One method to filter your array would be like this: arrayvar.Where(Function(x) x.ToUpper.Contains(variable.ToUpper) )(0)
and use that filtered item into the Item property.
I’m not really sure.
Here were some example solutions to get the items from a combobox:
Your error leads me to believe that your variable is of the wrong type, since it says “cannot convert from”. However, I’m not sure. If you provide some screenshots of how you are using the activities and variables it might help. It also depends on the website, like sometimes you can’t use the Get Attribute in this way.