is there any option in mit app inventor to create extension
i do not prefer niotron
have you searched the forum?
Here are some keywords: template, or rush, or aixc
where is the forum
Where are you asking questions?
i am new here so i do not know many things
Please search the forum before you post questions. Most likely your question has already been asked before, especially this one. There are a lot of tools where you can create extensions.
For beginner extension developers I recommend Niotron IDE. It is the best online extension development tool without any installation. For others like Rush and AppInventor Sources, you need to install Java and/or Apache Ant.
Nethertheless, I suggest you familiarize yourself with App Inventor itself before you create extensions. Start with some basics since extensions are something advanced.