API keys are general, meaning one API key can be used for GPT 3.5 TURBO, GPT 4, Dall-e etc.
If you don’t wanna use GPT 3.5 you can specify this in your code while developing application.
{
"model": "gpt-4-1106-preview",
"messages": [
{"role": "user", "content": "<prompt-start> <prompt-before-input1> <input1> <prompt-before-input2><input2> <prompt-before-input3> <input3> <prompt-before-input4> <input4> <prompt-before-input5> <input5>"}
],
"max_tokens": <max-tokens>,
"n": <number-of-renditions>
}
Under “model” you can specify gpt-4-1106-preview or any other model you are using.
In your usage tab should appear GPT 4 usage. Hope this helps.