Details and uses of all templates.

Short answers ...

Templates are customised to suit your own needs.

There are quite a few to consider ...

Template part models - Often containing a csys, default planes, maybe axes, points or other non-solid geometry. Often containing some number of pre-defined parameters.

Template assembly models - Again containing datum features (geometry), maybe a pre-defined skeleton part.

Template drawing sheets - different sizes with pre-defined formats.

Various configuration files - For setting-up the Creo working environment, units of measure, location of files (resources), etc.

You can go much further, you can build very complex assembly models containing hundreds, or thousands of parts, and use these as templates. It is a common practice among manufacturer's of large complex industrial machinery to use large assembly models as templates.

And yes, specific information included in the template gets embedded in the files. Additional data may be added or existing data changed in the course of your design progressing. This will all be stored.

Creo has many very powerful features and takes a lot of effort to master, if it can ever be mastered!

My advice is to get a good understanding of the fundamentals and keep on building from there.

This is a good place to get help with your questions.

If you do some research before asking, you'll be much more likely to get the best answers.

Good Luck 🙂