added info for the nf-core training

sites/main-site/src/content/events/2025/hackathon-march-2025/robert-koch-institute.mdx

@@ -24,7 +24,24 @@ Local event to be held at RKI, Berlin.
 Attendees from outside Robert Koch Institute **can** attend.
 
 -   [<i class="fab fa-slack"></i> Marie Lataretu](https://nfcore.slack.com/team/U04EL1VEY5C) ([[email protected]](mailto:[email protected]))
--   [<i class="fab fa-slack"></i> Paul Wolk](https://nfcore.slack.com/team/U04U4JKTB27)
+-   [<i class="fab fa-slack"></i> Paul Wolk](https://nfcore.slack.com/team/U04U4JKTB27) ([[email protected]](mailto:[email protected]))
+
+### Optional nf-core training: A practical introduction to nf-core components for Nextflow developers
+
+On the first day of the Hackathon, nf-core core-team member James A. Fellows Yates ([@jfy133](https://nfcore.slack.com/team/UEM37TBAR)) will give an (optional) on-site half- to one-day training on how to use nf-core components in your own Nextflow code.
+
+The scope is:
+
+- What is nf-core
+- Introduction to the nf-core community and tooling
+- How to create a nf-core module
+- How to use/install modules in your own Nextflow (both nf-core and non-nf-core) pipelines
+
+This is *not* a Nextflow training. Participants are expected to have some Nextflow experience in writing small Nextflow pipelines and should be familiar with the content of the [Hello Nextflow training](https://training.nextflow.io/hello_nextflow/).
+
+Please note that registration at the local site via the [Hackathon registration](https://seqera.typeform.com/nfcoremarch2025) is still necessary to join us on-site!
+
+Please register [here](https://terminplaner6.dfn.de/de/p/2c30b03745d9f646c2efbd31b02732e3-1078800) for the one-day nf-core training.
 
 ### Food