You will be asked if your thesis has been examined and if you have applied for it to be withheld.
You will be asked if you have clearance for all third party content.
If you select "No" you will be asked if you have a redacted version of your thesis.
If you do not have clearance for all third party content you are asked to supply two copies of your thesis. The first will have all third party content you do not have clearance for redacted. The second will be un-redacted.
Also you must redact any personal contact details and signatures (in any part of the thesis; even in ethics approval letters).
Once you are able to answer yes to one of the two previous questions you will be asked to select the collection. This will be either Doctoral theses or Master's theses.