Should I leave my Bitcoin forever without selling it or set a goal that I have in mind and when it reaches that goal I sell and take my profits?
Depending on you, as people do sell even when they aren't profitable for various reasons. Therefore, it all depends on the individual. At some point, the price will reach a place where you can sell, take your profit, and either wait for the next bad market or sell some of it and keep the remainder. Spot traders will also set a price restriction, and when an item reaches or even touches that price, it will be sold.
Nobody on this forum has the right to dictate what you do with your Bitcoin by the time he hits a target that you're okay with. You will Always hear people talk about hodling bitcoins for as long as possible, the "as possible" from that statement means to the point when you are okay with hodling and then decide to sell off some for other purpose.
While hodling your bitcoins, have a target and a purpose for hodling, having a target or a purpose for hodling can be something to motivate you into hodling more.
People will spend their money as they like, so the main thing to keep in mind when deciding whether or not to sell is if it is worth selling right now. With bitcoin, there are always surprises in store, and the price will increase at some time. And you have my wager. It's going to hurt you. Selling is the ultimate goal of investment, therefore even if you even generate a profit, you can sell. As I don't really think keeping for a long time makes sense, if you are receiving what you want, there's no harm in selling.
Holding also indicates that the price is low and will rise, which is why it is usually emphasized to people to hold. The best thing is, as you mentioned, to establish a target and, if the moment is right, to sell.