1. to plan something, to set an intention ("sich+Dat etwas vornehmen" - refers to the moment of setting the plan, not the period of having it. Mostly used in context of personal plans, like changing routines or stuff like that. NOT for schemes.)
2. to do, to make (Quite rare and only in a few contexts like for example making corrections or tackling problems. Sounds super formal and no one uses it in daily life)
3. to tackle, to confront ("sich+Dat jemanden/etwas vornehmen" - can be used for tackling a task or topic or for confronting a person, often with an undertone of giving them a scolding.)
