No direct conversion exists for free (or paid).

The landscape of mod conversion tools is evolving rapidly. The PortKit project, for example, aims to achieve a "one-click" AI-powered tool that intelligently converts Java Edition mods into functional Bedrock Edition add-ons using smart assumptions to bridge technical gaps. The development of multi-agent AI systems and improved validation tools suggests that conversion rates will continue to improve.

Rename your .jar file to .zip and extract it using software like WinRAR or 7-Zip.

Double-click the .mcaddon file to open it with Minecraft. The game will automatically import and install the add-on. Alternatively, you can place the file in your Minecraft's com.mojang folder.