No other player can make up for Kevin DeBruiner's absence. Haaland will suffer somewhat in attack due to his absence. But under the leadership of Pep Guardiola, a unique coach, Manchester City can surely come out of such problems.
Of course this is bad news, their prediction if De Bruyne can only recover at the beginning of next year. That means there are 4 months more he has to rest. Silva and Stones are also injured, so Pep can take advantage of the transfer moment that is still open at the moment to dance in De Bruyne's replacement. No option has been said by Pep yet but he has said, finding a replacement is the best option because 4 months is not a short time.
Source:
https://www.standard.co.uk/sport/football/man-city-injury-update-silva-stones-de-bruyne-latest-news-return-dates-b1101831.html