API Request Failed in cloudflare

i am recieving this error and i can not configure any setting .
API Request Failed: PATCH /api/v4/zones/bdd0bbb426a5f9bf23add76f6073d6de/settings/security_level (403)

API Request Failed: POST /api/v4/zones/bdd0bbb426a5f9bf23add76f6073d6de/purge_cache/ (403)

i want to change security level to " i am under attack " mode and see these errors

403 means you made a mistake in your client’s authorization. Make sure you’re either using an API token via the header Authorization: Bearer <token> or your global API key as described at Cloudflare API v4 Documentation. If you use an API token, it needs the permission zone ->zone->edit.

ok what can i do for solve this ?
please help
what is first step to do?