This is the 3489th most frequent Korean word.
많게는
"As many/much as."
It denotes an estimated upper limit or maximum quantity in this context.
많게는 하루에 백 명까지 올 수 있습니다.
As many as one hundred people can come in a day.
Here, it emphasizes the potential frequent occurrence of an action.
많게는 여러 번 반복해서 연습해야 실력이 늡니다.
You may need to practice many times repetitively to improve your skills.
It illustrates an extended duration or quantity to emphasize preparedness.