Unfortunately I don't think we have a form or button in the UI currently that does this. Creating YAML files and applying them using kubectl is probably your best option.
One of the challenges of the Release object is the "data" field, which accepts arbitrary YAML [1]. The content of the "data" field is passed to the release pipeline, which is expected to consume this information during the pipeline execution. What data is needed, and how it is processed, is up to you as a Konflux administrator. The "tenant pipelines" article has some guidance on how this works, and what is required if development teams want to create and manage their own release processes [2]. We just started curating example release pipelines in the community-catalog repo [3] if you want more examples/inspiration on how to write a release pipeline.