sql server – Deleting all the content from the database

We want to clean a database (delete all the records) with around 25 tables and a size of around 650+ GB in production. We are currently using MS SQL 2016 Standard Edition with AlwaysON HA.

Is truncating all the tables the best option, if not what is the best and fastest way to do this?

What is the potential time it is going to take for cleaning approx 650 GB of data?