GPT 3.5 Turbo Pricing clarification

I need clarity if 3.5 turbo model 16K context paid version can be used in chat.openai.comm. Because i am going to subscribe for the paid version and am only going to use the chatgpt chat interface and not the API. So want to be sure before i go for its purchase.

ChatGPT plus does not upgrade the gpt-3.5 model used by free ChatGPT.

It does give access to gpt-4, which has twice the context length, though, at 8k.

The conversation management used within ChatGPT is not as lossless and lengthy as you could program into your own API chatbot that could take highest advantage of the model, at increased expense if you want maximum conversation memory.