[Docs] Add instructions on LLM API providers

[Robbo-lab]

Issue Type

• [ X] Documentation update

Description

Create a section in the README which has links to the offical instrcutions on

OpenAI
Azure OpenAI
Google Gemini
Anthropic
Mistral
Cohere
AWS Bedrock
Groq
Together AI
Hugging Face
Fireworks AI
Bedrock
Vertex AI
Replicate
Eden AI
Portkey
DeepInfra

Possible Solution

Table of links plus estimated fees