ClearAll[ct, FunctionMatchQ, ValidFunctionQ, ProcessString]
ct = "add 1  alter 3  backup 2  bottom 1  Cappend 2  change 1  Schange  Cinsert 2  Clast 3
   compress 4 copy 2 count 3 Coverlay 3 cursor 3  delete 3 Cdelete 2  down 1  duplicate
   3 xEdit 1 expand 3 extract 3  find 1 Nfind 2 Nfindup 6 NfUP 3 Cfind 2 findUP 3 fUP 2
   forward 2  get  help 1 hexType 4  input 1 powerInput 3  join 1 split 2 spltJOIN load
   locate 1 Clocate 2 lowerCase 3 upperCase 3 Lprefix 2  macro  merge 2 modify 3 move 2
   msg  next 1 overlay 1 parse preserve 4 purge 3 put putD query 1 quit  read recover 3
   refresh renum 3 repeat 3 replace 1 Creplace 2 reset 3 restore 4 rgtLEFT right 2 left
   2  save  set  shift 2  si  sort  sos  stack 3 status 4 top  transfer 3  type 1  up 1";
ct = FixedPoint[StringReplace[{"\n" -> "", Longest[" " ..] -> " "}], ct];
ct = StringSplit[ct, " "];
ct = SequenceReplace[ct, {x_, y : (Alternatives @@ (ToString /@ Range[1, 9]))} :> {x, ToExpression@y}];
ct = If[MatchQ[#, {_, _Integer}], #, {#, 1}] & /@ ct;
FunctionMatchQ[{func_String, min_Integer}, test_String] :=
 Module[{max, l},
  max = StringLength[func];
  l = StringLength[test];
  If[min <= l <= max,
   If[StringStartsQ[func, test, IgnoreCase -> True],
    True
    ,
    False
    ]
   ,
   False
   ]
  ]
ValidFunctionQ[test_String] := Module[{val},
  val = SelectFirst[ct, FunctionMatchQ[#, test] &, Missing[]];
  If[MissingQ[val], "*error*", ToUpperCase[First@val]]
  ]
ProcessString[test_String] := Module[{parts},
  parts = StringSplit[test];
  StringRiffle[ValidFunctionQ /@ parts, " "]
  ]
ProcessString["riG   rePEAT copies  put mo   rest    types   fup.    6       poweRin"]