On IPhone ….
Open opera Gx then
Open or search the page you want
From the search bar > Let it load > Then from the bottom tabs bar on your opera browser > Select the Opera logo on right hand side > click the double circle type logo > Then Click the star > Select
Add to Home Screen …..
Your Bookmarked site should be below The Top sites >> In Favourites on your Opera Home Screen.
Hope this helps ..