become easier to access
Example: In the last 20 years China has opened up to international trade.
For more meanings of the phrasal verb open up
, follow the link.
To go on to something is to progress.
Example: He went on to university and then became a teacher.
A stepping stone is a stage of achievement or an event that leads on to something else.
Example: Doing a postgraduate honours year is a stepping stone to a PhD.
et cetera; and so on; other things like that
Example: I like driving anything fast - motorbikes, speedboats and that.