YouTube how to make first app

I’m following the step by step tutorial on YouTube for how to build an app. I’m in lesson 2 auto layout. I have created 3 buttons and added backgrounds. The first sign in with Facebook button looks way smaller than the other 2. How can I fix this, any thing I do, it starts giving me red mark errors.

Sorry if this is a silly question, just getting started.

I remember following this tutorial and everything worked OK for me. Sounds like you may have missed something so maybe go back over the video again.