Can’t delete emails on iPad .

I have tried repeatedly to delete emails from the mail icon on my iPad. I have a gmail account that shows all mail. The all mail folder continues to grow even though I have deleted over 1000 emails. I can’t find an archive folder. I see my email address in the cc line but don’t understand how my address got there. I have emptied my trash and spam folders. There are 6604 emails in the all mail folder. I am getting notices that I won’t be able to get new emails due to no more space