You should ALWAYS set a stop, ideally at the same time that you buy the stock. Look for a firm level of support. Imagine your stop there. Now look at the price. It is really nice to have your buy-in price just above that. The idea is if the stock falls below support, it is likely to keep falling quite a bit. So that is a good place for your stop. The bigger the difference between your entry price and your stop, the more loss you suffer if it stops out. If the price is barely above support, your risked amount per share is low. If it is a considerable distance above support, then your risk is considerably greater. But you still want your stop below that support level. Sure, you can move your stop up, but your chances of getting stopped out are greater.
Once you set your stop, and you are satisfied that it is at a logical level, do not move it down. It is okay to move it up, when the price has gone up a lot. Many traders like to set it just above their break-even, just to lock themselves into the profit side, and then move it up as the stock price rises, to lock in maybe half, maybe 2/3 of the profit. Some traders like to use trailing stops. As the price goes up, the trailing stop automatically follows, a set distance below the stock price. If the stock falls, the stop price stays put. If the stock starts going up again, once it has gone up more than the trail amount, then the stop starts going up with it again. If it turns around and goes down and keeps going down it meets the "stuck" trailing stop, and you get stopped out of your trade at whatever level the trailing stop has risen to. I prefer to move the stop up myself, setting it just below new levels of resistance or just below whole or half dollar amounts. However, when I can't watch a stock I will use a trailing stop if that type of order is available to me.
If you are very sure of your level of resistance, then by all means, set a profit limit just under it. That will maximize your profit if you pick the limit price correctly. However, you will usually find that a good stop is more effective than the limit because it will still limit the amount of profit you will give up, no matter what. If the stock does not touch your limit, then it is free to nosedive and there goes your profit if you didn't lock some of it in with a stop. Usually you can set a bracket order, which is a stop and a limit combined. When one is triggered, the other is automatically cancelled. I usually don't use limits because too many times, a stock will run, breaking through the resistance after poking it a few times. By setting a limit I am limiting my profits when I could have made a lot more.
Be aware that if your stop and limit are not in a one cancels the other arrangement, you could sell with your limit order, and sell again (short) with your stop loss when the stock goes back down. This could be disastrous, obviously.
I strongly suggest that you read a couple of good books on day and swing trading. You don't seem like you have read anything at all on the subject. If you have read some books, read them again. And again. Get these key concepts into your brain. Do your homework. Go back to your paper account and practice some more, using the methods you learn from your books. And remember, it is a lot harder to make money in real trading than paper trading due to real world issues. So don't think just because you traded a $100k paper account up to a million, you are ready for the big show. Keep your live positions small at first.