You can not delete User, but you can make them Inactive.
Yes, you can edit Users. To do so, follow the following steps
Step 1 - Click on Teams then select Users.

Step 2 - Click on the Activity button of the user and click on Edit to edit their details.

Step 3 - Edit required fields.

Step 4 - Click on Update.

Yes, you can edit Users. To do so, follow the following steps
Step 1 - Click on Teams then select Users.

Step 2 - Click on the Activity button of the user and click on Edit to edit their details.

Step 3 - Edit required fields.

Step 4 - Click on Update.
