The purpose of this study is to evaluate the safety, tolerability and pharmacokinetics of NNC0581-0001 in participants with hepatic steatosis and suspected steatohepatitis (increased liver fat and suspected inflammation). NNC0581-0001 will be given in 2 different dose levels as injection under the skin (once per month for 3 months). Participants will either get NNC0581-001 or Placebo (dummy treatment). Which treatment participants get is decided by chance. NNC0581-0001 is a new medicine which cannot be prescribed by doctors. The study will last about 58 weeks.