when I am filling things out via my phone the email that comes up is one of my contacts emails, not mine, I never send things to him nor have I ever used his when filling out anything so I cannot figure out how his has decided it is my default email and not the one I always type in? How can I fix this?
Go to your browser (Chrome, or whatever you use on your phone), then Settings for the browser (three dots or horizontal bars in the top corner of the app screen). Find "Auto fill settings" and scroll through what's there and delete the address you don't need.
Another place you can check is your keyboard settings, and your personal dictionary - it may have been added there. Settings > Language and Input > keyboard >Settings. Menu choices will be different depending on your specific keyboard, so check and explore all the settings.