If you wait 6 months your 1 Bitcoin will probably be worth $20,000 again or even more.
That is a mistake idiots always do, they mostly sell when a coin loses 40 or more %, never when is high.
If it was me, I would never sell for less than $18k.
I don't think anyone whould be telling him where he should start thinking about selling, when we don't know where he bought in. But yeah ... I wouldn't sell at 15K, if I bought in at 10K. And you certainly shouldn't consider selling now, if you bought in at 18K.
But if he acquired that 1 btc for 1K, I'm not going to tell someone that they shouldn't take a profit in fiat. Maybe not 100%, but do what you feel comfortable with.
I sold my btc when it was at 16k ( I bought it like one year ago ) so I have some money and I would like to invest in eth mining so guys if you have any recommendations please tell me or any other better crypto to mine