Can I place an order so that my account will buy 100 shares of stock xyz if it opens below my limit order but also place a stop loss on the same order so that I can contain my losses if the stock tanks after I buy?
Although this is possible with many brokers, it's not advisable. In many cases you may end up with both trades executed at the same time. This is because during the opening, the stock might spike up or down heavily, bid/ask spread widens, and both of your orders would get picked up, resulting in an instant loss. Your best bet is to place the stop manually sometime after you get filled.
if it opens below my limit order
What exactly are you trying to achieve here? If your limit order is for 100 and the stock opens "below" your limit order, say 99, then it is obviously going to buy it automatically.
also place a stop loss on the same order
Most brokers allow limit + stop loss order at the same time on same order.
What I conclude from your question is that you're with a broker that is using obscure technology. Get a better broker or maybe, retry phrasing your question correctly.
I don't mind taking a loss of a few hundred dollars but using the example of a certain stock that I bought at 2.64 per share on 8/14/18. On the next day it dropped to 2.41. At that point if I could have put in a stop order of lets say 2.30 I could handle that loss. I put in a limit order to sell at 2.74. The next day it made a drop to 1.76. This was a big loss for me. So I am very interested in not letting that ever happen again. I learned that the stop order should have been used in addition to my limit order to sell at 2.74.
From your question, I am guessing that you are intending to have stoploss buy order. is the stoploss order is also a buy order ?
As you also said, you seems to limit your losses, I am again guessing that you have short position of the stock, to which you are intending to place a buy limit order and buy stoploss order (stoploss helps when when the price tanks). And also I sense that you intend to place buy limit order at the price below the market price. is that the situation?
If you place two independent orders (one limit buy and one stoploss buy). Please remember that there will be situation where two orders also get executed due to market movements. Add more details to the questions. it helps to understand the situation and others can provide a strategic solution.