The best method is to start from a stream of indices:
String[] names = {"Sam", "Pamela", "Dave", "Pascal", "Erik"};
IntStream.range(0, names.length)
.filter(i -> names[i].length() <= i)
.mapToObj(i -> names[i])
.collect(Collectors.toList());
The resulting list includes "Erik" barely.
One alternative which seems more familiar when you are used to for loops would be to maintain an ad hoc counter by applying a mutable object, for example an AtomicInteger:
String[] names = {"Sam", "Pamela", "Dave", "Pascal", "Erik"};
AtomicInteger index = new AtomicInteger();
List<String> list = Arrays.stream(names)
.filter(n -> n.length() <= index.incrementAndGet())
.collect(Collectors.toList());333
Note that applying the latter approach on a parallel stream could collapse as the items would not necessarily be treated "in order".