I'd like to deploy React,nodejs project.

My project has two folder in big way, client, server. Sever project is written of node.js and I used mongoose also. client project is written of javasciprt while I'm in develop, I used local host and 5000 port for server, and 3000 port for client. And I used proxy for interacting between them. That time, npm run start, script makes server and client project are activated concurrently.

I did some process to deploy project.

1. I made ec2 instance.
2. I connect ssh
3. I cloned project using git.
4. I installed npm, monogod, nodejs

but I'm stucked with further steps. So, I have some questions.

1. how to deal with my dot.env file(It was used for api key(mongo, kakaomap)) ? should I make in ssh terminal?
2. In now, my address site show that they can't connect. should I install something else for connecting my project with them? I installed nginx but it's not work. it said I don't have authentication.