BitterLeopard33

How to create a parent-child Dataset with a same dataset_id and only access the child?

Dataset ID is unique, the child will have a different UID. The name of the Dataset can the the same though.
Specifically to create a child Dataset:
https://clear.ml/docs/latest/docs/clearml_data#datasetcreate
child = Dataset.create(..., parent_datasets=['parent_datast_id'])

Are there any ways to access the parent dataset(assuming its large and i dont want to download it)

What do you mean by accessing it, without actually downloadable the files? Is it listing ?
https://clear.ml/docs/latest/docs/references/sdk/dataset#list_files