To avoid losing your Swedish citizenship if you were born outside of Sweden and never lived in Sweden you can apply to retain it. You must do this after you have turned 18 but before you reach the age of 22. You will find the form here. Please book an appointment for your application. 

You must provide the following documents:

• Passport of the applicant
• Passport of the Swedish parent
• If the Swedish parent is born in Sweden and has moved to Israel,  you have to bring either "Certificate Attesting Israeli Citizenship" or "Confirmation of non-acquisition of Israeli citizenship" from the Israeli Ministry of Interior. An alternative is to show a residence permit/visa in Israel. 
• Please note that all documents must be in Swedish or English, or translated by a certified translator into one of these languages.

Note that you will not lose your Swedish citizenship if this would cause you to become stateless.