Is it possible and safe to buy an eSim from Maya for an Iphone and will I be able to use it in Italy and Croatia...and in english? Or is it better to buy a real sim card. What does it mean that a phone should be unlocked to use the eSim? Will i be able to use Google maps in the country where I am. Thanks
it isn't just "should" it is that the phone "must" be unlocked for you to be able to change carriers/SIMs.
If you got the phone (I have no idea who Maya are) as part of a phone subscription, you will be tied to that provider for a period of time. To ensure that you cannot leave them most providers (worldwide) electronically "lock" the phone so you can't change the SIM and therefore the provider. Well, you can physically replace the SIM but it won't work.
After a certain amount of time, depending on the rules of the provider that you signed when you got the phone, the phone will either unlock or you can ask for it to be unlocked (a very long string of characters is typed in, in a particular way, which electronically enables change of SIM or e-SIM) and then you can do things with your phone you couldn't while it was locked.
You may still have obligations to the carrier - it will depend on your contract.
Some phones in some countries are sold at full price in stores without a SIM and without a contract. That's how mine was sold to me, and you then look for the best deal on a SIM and put it in the phone and whichever network that SIM is from will be your new provider.
That's pretty much what you are doing when you add an e-SIM or replace the physical SIM. Then when you get home you put the original SIM back in and you get your original provider and phone number back.
If you replace the SIM you also change your phone number for the duration (some exceptions).
There is no difference in the data service provided by an eSim and a regular sim.
However most of the time a physical sim will include a new telephone number and many eSim plans may be data only. Once you have data, you can do whatever you do with your phone at home (Google Maps, Facebook, Messenger, WhatsApp, etc.).
You can also use WiFi for getting information.
I have not used Maya and it looks like their data plans are a touch higher than Airalo. Just double check the listing of covered countries in whatever plan you are looking at.