Hi Ania
Hosting people from other countries is no different to hosting people from your country. Make sure that you have set your reservation requirements to 'require verification' - that means that all guests will have given some proof to AIrBnB that they are who they say they are. Of course it's no guarantee of future or past behaviour.
Until you get used to hosting you may wish to consider only taking guests who have some reviews from other hosts (but about 40% of our guests are new to AirBnB - just like you!)
Other than that - ask questions so that you are comfortable with why they are coming to your area, what they intend to do when they are there, etc..