As i can see the date this OP was posted, i think the author may have tempted to sell (maybe some or maybe all) of his bitcoin midway through december when bitcoin's market value reached the 20,000$ mark. If he just let it pass and ignore it, maybe he is feeling a little regret knowing that bitcoin fall down from that mark to 11,000$+ today.
It's better to hodl it now strong and believe that bitcoin will come back again.

Given the situation, I will not sell my bitcoin if I don't have anything to buy or use the money on the moment and if ever I will, I will only sell only the equivalent value of of the price that I need, not all. I am sure Bitcoin's price will still go up in the future.

I understand your dilemma because it is also mine. My answer is that it very much depends how important would be for you the FIAT sum that you would get by selling. And if you are nor sure you can always decide to sell half - or less, to balance the risk.

I will withdraw my profit and leave the capital to hold. If the profit is much too high I will withdraw the capital and leave the profit. But if I have lots of spare money I'm not going to withdraw instead I'm going to add more to earn more.

I think every bitcoin holder’s dilemma is if bitcoin will be gone in a blink. Each and every one of us will surely be terrify if bitcoin will be gone in a blink. All our efforts, hard work, sleepless nights, and precious time will fly away in the wind. All our money that we invest in bitcoin will also be gone like a thief just stole it. Imagine that you have all your money and investment in your house then it burn out by fire. Well this is our dilemma but we are hoping that this will be just dilemma and it will not happen to us. 

If you keep your bitcoin today you probably lost a great deal of money. bitcoin prices from $ 20,000, have fallen and fluctuated at $ 11,000; Bitcoin prices increase very slowly, and may decrease further. The bitcoin market is already saturated. At present ethereum prices are rising, ethereum in the future may rise higher than bitcoin. This is my personal opinion.

I guess you have to decide and do the speculation. I think you can do a lot of ways to get around the current situation. you can trade with a cheap altcoin that has a pretty good future. there are many ideas you can do. you must have a plan and a strategy. try to find a lot of knowledge about which is related to crypto.

That completely depends on the personal outlook you have on this space.

Depending on what you do day to day, if you are busy or not, just focus on yourself and keep developing your skills. Let bitcoin sit in your portfolio and come back in a couple of years. If you dont need it right now then dont worry.

Ok Suppose I have some bitcoins ( let's say 22), suppose I am not going to buy more, I suppose sell half when suppose price btc 20k and suppose keep half. But I can only suppose.