Spring Boot - enable and configure SSL certificate

I have this certificates / files in order to enable SSL for my application:

Image may be NSFW.
Clik here to view.

I found out that this properties are needed for Spring Boot to enable HTTPS:

server.port=8089server.ssl.enabled=trueserver.ssl.key-store=src/main/resources/keystore.p12server.ssl.key-store-password=****server.ssl.keyStoreType=PKCS12server.ssl.keyAlias=tomcat

but this does not work. My question now would be what do I have to do in order to get it work? https://abc.lehr.co.at should be the URL.

[EDIT]

I have created my own keystore - with this I get the following exception:

java.io.IOException: Alias name tomcat does not identify a key entryat org.apache.tomcat.util.net.jsse.JSSESocketFactory.getKeyManagers(JSSESocketFactory.java:596)at org.apache.tomcat.util.net.jsse.JSSESocketFactory.getKeyManagers(JSSESocketFactory.java:534)at org.apache.tomcat.util.net.NioEndpoint.bind(NioEndpoint.java:363)at org.apache.tomcat.util.net.AbstractEndpoint.start(AbstractEndpoint.java:739)at org.apache.coyote.AbstractProtocol.start(AbstractProtocol.java:472)at org.apache.coyote.http11.Http11NioProtocol.start(Http11NioProtocol.java:81)at org.apache.catalina.connector.Connector.startInternal(Connector.java:986)

My keystore looks like this:

Image may be NSFW.
Clik here to view.

Actually I don't know what to import into keystore for embedded tomcat (Spring Boot).