Hi Shubham,
A connection can only be made between the AI Foundry project and the AI Foundry resource from different resource groups, as shown below:
In your AI Foundry -> Select Management Center -> Select New Connection -> Select Azure AI Foundry -> Then select Add Connection, as shown below:
Here is supported documentation:
https://free.blessedness.top/en-us/azure/ai-foundry/how-to/connections-add
Whenever you create a project inside any AI Foundry, it will require a resource group name, as shown below.
Currently, this are the only ways to connect and have a project from one resource group in another resource group's AI Foundry.
Feel free to accept this as an answer.
Thankyou for reaching out to The Microsoft QNA Portal.