Uploading Custom Bot in Teams Admin App

Please refer to the following Microsoft Documents for guidance on: 

1. How to Upload a custom app : https://docs.microsoft.com/en-us/microsoftteams/upload-custom-apps#upload

2. How to manage Access to that app : https://docs.microsoft.com/en-us/microsoftteams/teams-app-permission-policies#create-a-custom-app-permission-policy

Here is some additional details on App Permission in Teams: https://docs.microsoft.com/en-us/microsoftteams/teams-app-permission-policies#create-a-custom-app-permission-policy