How to configure the components in an image

Hi All,

I am new to Docker world so not able to understand initial steps.
Please suggest how to configure the components in an image.
PFB the dockerfile code for creation of image-

FROM tomcat:latest
FROM mysql:latest
FROM java:latest
CMD [“This is image completion message”]

How do we perform the activity like creation of databases, tables ,configuration of environment variables etc.

Regards,
Prateek