FullBright UB is a widely used pack that removes all shadows.
If you don't want to mess with text files, you can use a "Fullbright" texture pack. These are popular because they don't require Fabric or Forge to run. Fullbright 1.17
Simple Fullbright supports Fabric, Forge, and NeoForge, allowing you to toggle the effect instantly with a hotkey. FullBright UB is a widely used pack that removes all shadows
To get in Minecraft 1.17 , you essentially have three paths: editing your game files (no mods required), using a resource pack, or installing a dedicated mod. 1. The "No-Mod" Method (Gamma Editing) using a resource pack