If you need an instant temporary email address, you can use various online services that provide disposable email addresses. These email addresses are temporary and self-destruct after a certain period of time. Here are best popular option:
10 Minutes Mail (https://10minutesemail.net): Temp Mail allows you to generate a temporary email address instantly without any registration. It provides you with an inbox where you can receive emails for a specified period. The generated email address will be active as long as you keep the page open.
Remember that temporary email addresses are primarily intended for short-term use, such as signing up for websites or services that require an email verification. They are not suitable for long-term use or for receiving important personal or sensitive information.