Power BI Embedded React Generate Token key

Hello Everyone,

We are trying to develop a react application using this npm package.
https://www.npmjs.com/package/powerbi-report-component

I created a Power BI embedded environment via this link.

https://app.powerbi.com/embedsetup/

My organization don't have an azure account but our powerbi license is pro

I know these details: embedUrl, tokenType, accessToken 

Question 1: 

which token type should I choose? "Embed"  or "Aad" (we do not use microsoft azure)

Question 2:

Does the token key I use have to have a lifetime?

 Question 3:

Is it possible to generate token keys with username and password in the application? What's the easy way to do this?

What is the client_id in the example below? where can I get.

client_id
and which user should I connect to here?