Create Button

You can simply create your own button to create a new Card. You could use this buttons for example on a starting page.

First, add the necessary code. To do this, add a new Client Side Script Library. Add the following code inside the newly created Script Library below the var csl_key:

function guid() {
  function s4() {
    return Math.floor((1 + Math.random()) * 0x10000)
      .toString(16)
      .substring(1);
  }
  return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
    s4() + '-' + s4() + s4() + s4();
} 

function erstelle_antrag(){
    window.open("/aenderungsantrag/" + guid() + "?parent_card_key=83247195-b17b-45ab-b33d-91ed85261b09&parent_proto_key=65781473-b486-45f2-c63f-d91f1e998341&action=open_new_card&element_id=ef2b3ed1-1552-4ed5-fd53-a852e61fbd90&proto_key=2fb7193e-a1d5-48fe-a656-d2d9435fd135", "_self");
}

create a new trigger. Next, add a button to the Proto you like. I choose my starting page to add a button.