Do I have any obligations if I request a sole proprietor EIN in my own name?

I want to buy some stuff shipped from overseas for a small side project. This supplier wants me to supply a Tax ID which they say is for customs purposes; for stuff shipped to the US they specifically say they need either a SSN or an EIN.

I do not want to give my SSN to a random online vendor, but per my understanding I could request a personal EIN from the IRS.

If I don’t make any money from my side project, does having my own EIN on my own name come with any filing obligations? Do I have to do anything extra on my tax returns, file any information returns for it, or anything?

Additionally, as I understand I can only deduct the cost of the stuff I buy in case my side project has revenue, right?

If one day my side project does make money and I set up a single member LLC for it, can I use the same EIN for that LLC? As I understand it would be considered a disregarded entity owned by a US person and any income would be reported on my personal tax return.