Hi there and welcome
If the 'Send' button is missing you can add it to the 'Composition Toolbar'. Click 'View' > 'Toolbars' > 'Customise' Drag the Send icon onto the toolbar.
If that does not work, click on 'REstore default set' button in 'customise' window and its returned
I can also do these steps for you, and have made a request via Additional Services. This is optional, and if you choose to do this, I can, with your permission, remote into your computer while you watch and do all these steps (and deal with any problems that arise during them) for you. Or if you do not choose to take this service, we can continue here. This is no problem at all. Just let me know please.
Let me know the results please