Self-Employed question

Hi, I'm Self-Employed in the US, but I would like to open an office outside the US. It is related to the same business I have here, and I will be the only one managing it when I'm in that country. However, I will incur expenses (services and office equipment), how can I report those expenses?

 

Also, can you tell me where to pay my quarterly State taxes for Maryland?

 

And, the last question, my son had a daughter last year, but neither he nor I didn't report her in our 2022 tax return because she didn't have a social security number, because she was born in another country. We are requesting her social security number now. Do you recommend reporting her birth in the 2023 tax return when we know her social security number or amend the 2022 tax return because she was born last year?