Are you asking how to convert your old events, which you posted as blog posts, to events in the way the plug-in understands them? Or are you wanting to post a list of events on an already existing page?
If the latter there are three ways of doing this.
The first (and simplest) is to use the
[eo_events] shortcode. You can find documentation for it here: http://www.harriswebsolutions.co.uk/event-organiser/documentation/shortcodes/event-list-shortcode/
The next two are very similar but differ in the details.
One is to use
eo_get_events(). This behaves in exactly the same way as
get_posts() but sets a few parameters. If you familiar with
get_posts() (see codex) then you should be able to use
eo_get_events() (documentation for which can be found here: http://www.harriswebsolutions.co.uk/event-organiser/documentation/function-reference/eo_get_events/
The final method is to use
WP_Query(). This is very similar to
get_posts() (I explain the differences here).
These methods allow you to use all the 'normal' WordPress arguments when querying events (i.e.
tax_query allows to you select events in a particular category and/or venue). One top of that there are event-specific queries such as:
event_start_after - Events that start after certain date
event_end_after - Events that end after certain date
event_start_before - Events that start before certain date
event_end_before - Events that end before certain date
Dates can be absolute or relative (e.g. 'today'). More information on this can be found here.
These last two methods involve editing the page template being used - and while more involved gives you the greatest control over how events are displayed.