how to split a map based on user input value

hi [mention:92ba06295fbc4d77b281c512999a858b:e9ed411860ed4f2ba0265705b8793d05]  May I know what your use case is and what you are trying to achieve 

Your requirement is unclear from here.

Are you expecting two different dictionaries based on your input? Also what criteria are you looking at for the split. 

You can easily iterate on the input maps, and, based on conditions, create two new maps for each.

I am not sure what you are trying to achieve but here is the sample code that matches your requirement

a!localVariables(
  local!data: {
    a!map(
      id: 1,
      name: "Alice",
      age: 10,
      city: "New York",
      school: "NewYork"
    ),
    a!map(
      id: 2,
      name: "Bob",
      age: 12,
      city: "Los Angeles",
      school: "NewYork"
    ),
    a!map(
      id: 3,
      name: "Charlie",
      age: 13,
      city: "Chicago",
      school: "NewYork"
    ),
    a!map(
      id: 4,
      name: "David",
      age: 14,
      city: "Houston",
      school: "NewYork"
    )
  },
  local!keys: a!keys(local!data[1]),
  local!inputindex: if(
    a!isNullOrEmpty(ri!input),
    "",
    if(
      contains(local!keys, ri!input),
      wherecontains(touniformstring(ri!input), local!keys),
      null
    )
  ),
  local!keys2: if(
    a!isNullOrEmpty(local!inputindex),
    null,
    rdrop(
      local!keys,
      (length(local!keys) - local!inputindex)
    )
  ),
  local!keys3: if(
    a!isNullOrEmpty(local!inputindex),
    null,
    ldrop(local!keys, local!inputindex)
  ),
  local!data1: if(
    a!isNullOrEmpty(local!inputindex),
    null,
    cast(
      253,
      a!forEach(
        local!data,
        createdictionary(
          local!keys2,
          property(fv!item, local!keys2, null)
        )
      )
    )
  ),
  local!data2: if(
    a!isNullOrEmpty(local!inputindex),
    null,
    cast(
      253,
      a!forEach(
        local!data,
        createdictionary(
          local!keys3,
          property(fv!item, local!keys3, null)
        )
      )
    )
  ),
  {
    if(
      a!isNullOrEmpty(local!inputindex),
      "Enter right keyword",
      { local!data1, local!data2 }
    )
  }
)