We use Discord for voice chat, dice roll with the
Sebedius discord bot (written by user Stefouch).
We then use
Miro for files, pictures, drawing maps, using screenshotted references from rule books and so on. Miro in its simple form is free if you use 3 or less boards. If you make a fourth board, the oldest board becomes "read-only" and can no longer track changes. Think of it as your table if you were to play at home around your kitchen table. It is super simple to use and does everything we want.
There's a built in chat and video conference-function in Miro but we've never tried it and I'm not sure if it's included in the free plan either.