I'm not trying to join the bandwagon to compare between Hojlund and Haaland. but clearly, these two players are on different levels. when Haaland played for Dortmund, there were many big clubs who wanted his services. well, it can be said that now Halaand is an established striker.
So far Haaland is far better than Hojlund but in football, sometimes a player does not have good signals to be a great player when he is young but later he suddenly grows up and becomes a great player. They have a short period at top levels than players who are star players at young ages but during such short period, they can be one of greatest. Luca Toni in Italy, Jamie Vardy in England are good examples in the last 20 years and Hojlund is still young to repeat such success. At least he has a chance to play for a big club when he was young.
As Ten Hag said on several occasions, if Hojlund could be much more developed. He also has huge potential, now it's up to him to explore his talent and we will support him. which in essence, now that Manchester Unted has a player who plays as a center forward, they no longer have to rely on Marcus Rashford.
Hojlund will have to be more serious with his training, learning from videos and players in a same club, same league to sharpen all his skills including improve his weakness and try to strengthen his best skills.
I see many people comparing these two layers in the premier league and since their names are even similar and both players are young were right to compare Haaland and Hojlund. However, Hojlund is much cheaper than Haaland but I think Hojlund can have a good performance in Manchester United with Ten Hag because Ten Hag is famous for his hard training and if this happens we are going to see an interesting race between these two players in the next season in both premier league and champions league.