Cypress how to use api key in put/post request?

There are few options you can try, Here is one :

cy.intercept('POST', '/users*', (req) => {
  req.headers['x-api-key'] = 'bearer my-bearer-auth-token'
}).as('addAuthHeader')

Refer Offical Link here: https://docs.cypress.io/guides/guides/network-requests#Assertions

I was able to resovle it syntax is: authorization : key + value no quotes –

You can use cy.request. Although not outlined in the docs, it accepts an object:

cy.request({
  method: 'POST',
  url: 'https://jsonplaceholder.cypress.io/',
  headers: { 'x-api-key': 'APIKEY' },
}).then((res) => {
  // use the response with response.body
});