It's not possible to send pictures to an email. If you use the built in Mail app, you can insert photos and send them per email.
Every other email app (Gmail, Inbox, Yahoo Mail, ...) needs your allowance to be able to access your Photos app.
What exactly are you trying to do? Maybe we can help when you describe your problem more precisely.
I am using the mail app in my phone. I choose the pic I want to send & click on the option to send to email. I choose the size, then hit send. I hear the "whoosh" like it is being sent, but it never arrives. I have done this in the past & it worked fine, but now it no longer does.
Is this only happening when you try sending pictures?
Here's what you can try:
Go to your settings on the iPhone, Mail, Contacts, Calendars. Select the email address that doesn't send photos, and take a look at your settings for the outgoing mail server, if it's possible to view them.
Another method to get rid of problems with an email account, would be to remove the account completely, and reinstall it.