I am intending to submit a paper to the Oxford University Commonwealth Law Journal and I am referring to data from my thesis. I understand I can deposit it in a repository. Please advise how to do it.
Sure thing. Super easy. Sign up here for free: https://figshare.com/account/register , upload your files and add metadata, publish! Then when published, you can navigate to the public page to get your DOI. If your use case is more complex than this, there are other ways we can help but let's start here
In short, yes
The first method is a recipe for setting up an automatic Zenodo-GitHub integration we currently have in Zenodo, but in the end it can be done manually for any software repository, even if it lives only locally on your machine, i.e. you can upload a zip-ball of your software to Zenodo, provide some metadata and publish it to get a DOI (just as you would if you uploaded a paper or data).
Having said that, it’s probably the best if you make a zip-ball of a tagged release, so that the DOI captures something “complete”. Additionally you can supplement your record metadata on Zenodo with a “related identifier” (e.g. a URL) and point back to the tag on your live repository. This way anyone who discovers your software in the future will also have means to follow your live repository and find the most recent version of the software.
What code can I use if I want the data to be privately stored?
You don't need to use any code. You can just upload your data and it's private by default. You can then share with a private link if you wish before publishing and also you can reserve a DOI to add to any relevant papers before publishing. All of this is accessible on the create item overlay in My Data once you create and account.
Although the site is not currently mobile optimised. all functions should work, especially on android with access to the file system. What in particular are you trying to achieve you are having troubles with?