We suggest you use app-only token to silently make requests. It's not possible to get other user's token without user interaction.
You may take a reference of :
client credentials flow
Resource Owner Password Credentials
You're not able to operate under a specific account until the corresponding user provided delegated permissions to your Azure app. So, first, you must register an Azure app, request delegated permissions from each user you want to get access on behalf of, and save access and refresh tokens on your side. Then, you can make requests with those tokens.