Manchester City perform well in Premier League in recent seasons, without Haaland. They need Haaland to win Champions League, not Premier League. They already dominate Premier League and Liverpool can not beat Manchester City in many seasons.
I think Haaland in theory is very good to play in Premier League and with the whole attacking system of Manchester City, Haaland will receive many good key passes from his mates. The rest part is finishing such passes and converting them to goals. I do not doubt that Haaland will fail to convert chances to goals.
City didn't have one big striker, they all scored a little bit of De Bruyne (15), Sterling (13), Mahrez (11), Foden (9). Guardiola has an attacking tactic, with such a strategy it is clear that the team can score many goals, but if the task has become to find a striker (Haaland), then Guardiola sees this as a necessity, and as a result of an increase in the implementation of scoring chances. City players will create a large number of scoring chances for Haaland, there is no doubt about this, the most important thing is to skillfully implement them.