Hitboxes can be shown in both the java and bedrock editions of Minecraft.
Hitboxes in Minecraft outline living things or mobs in the game. The hitbox also applies to players and their friends. The hitbox will include a red line that wraps around the middle of the head of a mob where its eyes are. The red line in a hitbox indicates the line of sight for the mob. A blue line can be seen in front of the mob to show where the mob is facing. Green boxes on the hitbox of the ender dragon are an indicator of where a player can damage it.
Hitboxes can be used by players as guidelines for hitting a mob in the game. If the hitbox doesn't cover the entire mob, the parts that aren't on the hitbox will not affect the mob if hit. An example of a mob that has parts outside of the hitbox is ghast. The tentacles of a ghast are shown outside of its hitbox. Players can also use different colors hitboxes to deal damage in boss fights such as fighting the ender dragon.
How to show hitboxes in Minecraft
Hitboxes in Minecraft's java edition can be seen by pressing the F3 key and B key at the same time. Pressing those buttons will cause the player to see the hitbox on other things in the game. The key combination to show hitboxes is for the java edition only. The F3 and B key combination will not show the same result for bedrock edition players.
Bedrock edition players will find that the F3 key and B key combination will cause an emote wheel to pop up instead of hitboxes. Players using the bedrock edition of Minecraft will need to download a hitbox modpack and import it as a resource pack. Once the player has imported the file, they can select the mod through their settings in the global resources section.