Starting new business - requesting advice

Hi there,

I have been borrowing my mom's personal money to purchase items to start a business where I build products and put them up for sale. I have not made any profit yet, but hope to do so in future. But it just occurred to us that I may save on taxes as well if I formalize this as a business and submit all those expenses, losses and profits. I heard the word LLC from someone, but not sure how to go about or if there is something else I need to do. Also, should I have done this before I purchased those items or can I still submit those expenses when I file my tax return next year via TurboTax? I would appreciate any advice as we have no knowledge nor  experience in this matter. Thank you so much.