Maybe I am not seeing it but in iPad when I am writing an email is there an icon like a paperclip to touch when I want attach a photo?

Remember, search is your friend!

To answer your question, no there is no "paperclip" to attach files in the iPad's Mail App. In short, you can email files directly from the App you're using...Photos, Pages, etc. The option to email files exists in almost all apps (that use files). Once you tell the app to send a copy of the file in question an email will open automatically and you send it from there (providing you have an email account set up on your iPad).

Here's a primer regarding email attachments when using your iPad...

How to email photos and other attachments