Hi, I'm new here, I would like to know where can I find detailed plans in metric for a forge press( I'm a budding knife maker)

You may want to look at South African Highveld

Any plans we suggest may be of no use to you in South Africa, as it would suggest parts not available in your part of the world. 

It would be more useful to tell us what you have to work with, if the want to have the press turn key, fully built and working, or just how much you can build on your own.  Do you have a welder and can you make structural welds for instance.

Are you interested in a hydraulic press, screw press, fly press, or mechanical press?  Have you looked at the section on hydraulic presses, fly presses, etc which has 7.3k posts?

Have you looked at the section on bladesmithing?  Pay particular attention to the sub-sections Knife Making Classes,
 Knife Making Class 101,  Knife Making Class 200, and Knife Class Reference Material.