You can download your dataset from the corpus builder in the link shown below. (You may also have a link to your dataset in your email.) If you wish, you can modify your dataset on your local machine before the next upload phase. This gives you some more flexibility than automatically pulling in your dataset using a dataset ID using option 2 below.
Once you have your dataset ready on your local machine, you can then upload your dataset into JupyterLab by clicking the upload button in the file pane on the left.
Make sure to upload your dataset to the "datasets" folder.