I am going to work in America for 3 months! I'm very excited about it, or at least I was until about a week ago but now I'm full of anxiety about the whole thing. 
I've never flown abroad on my own before and I'm so anxious about the whole process. So I was wondering if anyone knows how it all works? How do I get my boarding pass? What info do i need to check in and drop my bag off? How does my suitcase get to the other plane during the layover? (Im changing at Philadelpha Airport) 

Note: because my work has this stupid policy I have to use a travel agent, and I hate them having control of everything. All I have is an e-ticket from them and I don't know how to make that into a boarding pass.

If anyone has travelled to the US recently and could give advice, it would be greatly appreciated just so I feel like I know what's coming. Thank you 🙏