To set these permissions the teacher needs to simply create the teams meeting for their class to start with the normal way.
Once the meeting has been setup, the teacher then needs to go into their calendar and open the meeting they just created, once open there is a 'meeting options' option further down.
Click on this and it will open the meeting within your browser.
Once the meeting options have loaded, set the options to those shown in the image below:
This will prevent the students from joining the meeting without a teacher present, prevent the students from kicking other students out, muting\unmuting themselves and others :)