I have had expensive auto darkening hoods & I have the inexpensive Harbor Freight $40 auto darkening hood. If you are just starting out, The HF will do you just fine. I can normally get a couple years out of one before the rechargeable lithium battery goes out. The HF sheild adjusts from a 9 to a 13 shade. You can also get 3 pr of welding gloves from them for $8-12 depending on sales. Occasionally I will get a pair which don't hold up well, but when you get 3 pr for the price of one, I can't complain. They will also have chipping hammers, soapstone holders & leathers.
I agree with prior post recommending not sharing equipment for health reasons when ever possible. A grinding shield is fairly cheap and a cap to wear with your welding shield is a very smart investment.
Not to discourage you, I applaud anyone who tries to better themselves, but it is not uncommon to start a training program & find for one reason or another, it is not a good fit for you. I would not go over kill buying accessories/tools for welding until you feel confident it for you. Light sensitivity, wearing contacts with history of dry eyes, fumes from welding & grinding especially dirty/painted/galvanized metal can really effect one especially if they have a history of respiratory problems.
I wish you the best!