Ah, no. It’s a very common point of confusion, unfortunately.
you have a paid plus account on chat.openai.com, where you can access chatgpt “GPT-4”, with a 40 messages /3 hour limit.
but you’re trying to access platform.openai.com, the developer API - where you have to prepay, and will be charged for every call, depending on how many tokens you send and generate.
check out the sidebar on platform.openai.com
if you check usage, you will see a dashboard where you may or may not have been given a grant of a couple of dollars to get started.
if you want to move up in tiers you will need to visit billing and add some money. Do note that there’s a time restriction for higher tiers, as detailed in the rate limits: https://platform.openai.com/docs/guides/rate-limits/free-tier-rate-limits
Oh yeah, and if you’re new to all this:
/!\ if you give someone your API keys, they can spend all your credits! beware! /!\
Even developers are often struggling with leaked keys. Use caution!