This is a very common question online, both on Twitter and many Facebook groups.
If you live outside of urban areas, there are many places to fly your drone. Generally this is referred to as Class G airspace and is largely unrestricted up to 400ft.
In towns and villages and cities, it gets more complicated. Lets take Dublin for example. Largely due to Dublin Airport, almost all of Dublin County is covered in controlled airspace, or Class C. You can still fly your drone in most open areas up to a maximum of 50ft/15m above ground level. Above this, you require Air Traffic Control clearance, as there can be many forms of manned aviation above you that can appear quickly in the airspace around you. The Garda Helicopter is a good example of this. To be able to apply for permission to fly above 15m, you need an SOP or Specific Operations Permission from the iAA. We will cover that topic separately, but there is a very useful interactive drone airspace map at the link below. Check out where you can fly.
Remember, its not just drone laws you need to be aware of. Data protection is very important, so familiarise yourself with the requirements, and of course, you need the landowners permission for where you take off and land, otherwise you are trespassing.