Evaluate the Safety and Pharmacokinetics/Pharmacodynamics and Food Effect of HS-20118

The study will be conducted in 2 parts (SAD and FE for Part 1 and MAD for Part2). Part 1 is a single-center, randomized, double-blind, placebo-controlled, SAD study to evaluate the safety, tolerability, immunogenicity, and PK of HS-20118 and explore the food effect and fasting time on PK after a single oral dose in healthy participants. Part 2 is a multi-center, randomized, double-blind, placebo-controlled, MAD study to evaluate the safety, tolerability, immunogenicity, PK, and PD of HS-20118 after multiple oral doses in patients with moderate to severe plaque psoriasis.