Why you don’t just tell the method … ?
Step 1 : Go to This Website: https://tempmail.dev
You will see a Temporary Edu Mail then follow the next steps, if you don’t see an email with .edu then simply click on the Delete icon Unless you get temp .edu extension. Email should be something like this -
Step 2 : Go to https://www.canva.com/edu-signup
Sign up with that temp email and verify the Email.
After confirming you can edit a temporary email to your Gmail account directly from canva (But it can ask you to verify to your identity)
NOTE - its not my method (Made by another site)