A worldview is not exactly "having opinions on various issues".
One can have opinions on various issues, and those opinions not be connected to any worldview.
Your worldview is however, made up of a culmination of ideas, views, opinions, philosophies, etc., all combined into one overall view.
Think of it like a person who is headed one direction.
The person is going that direction because he does not like colored people. He does not like too much sun. He want to have access to clean water.
His worldview is shaped by the various ideas, and views he has.
It would be more accurate to define a worldview as an accumulation of those opinions, ideas, views, etc.
Am I confusing you? I don't mean to. Sorry.
...and yes, ones worldview can determine one's opinions on various issues, as
@Augustus said... Only after the worldview has been shaped.