Yes you are right.
It's more like "Written Korean"
앞으로 걸어갈 시간 = " The time you will spend" , " The future you are going", "The time you will walk along"
앞으로 나아갈(나아가다 -> 나아가+ㄹ) 시간 = " It's time to move forward", " we didn't go forward yet but it's about time to do"
안으로 들어갈(v.들어가다 ->들어가+ㄹ)시간 =" It's time to get in", " We didn't go inside but it's about time to get in(or jump it or go inside)"
Hope you understand