8 days for young boys are more than enough to see a lot many places. In 2001, we visited Hunza, Khunjerab, Skardu, Shangrila, Fairy Meadows, Naltar in 8 days.
A suggested plan for u is as under:
Night of Day 0: Start from Rawalpindi at night (around 9-10pm) on Natco or any other transport. Once Silk Route Bus was very good. I am not aware of their condition or existence now.
Day 1: InshaAllah u will reach Gilgit around noon ( or even before). Immediately get on the bus/van to Hunza. Stay at Karimabad Hunza
Day 2: Early morning, catch a van for Sost. On reaching Sost, negotiate with some jeep or car etc for Khunjerab. Visit and enjoy Khunjerab and be back to Hunza for night stay. If time allow, u can even come to Gilgit.
Day 3: Travel from Hunza or Gilgit to Skardu. If u start early morning, u will have enough time to visit Shangrila (and even upper kachura) on same day. In the evening, negotiate and finalize the deal with some jeep driver for Deosai. Buy essential supplies for next days.
Day 4: Leave for Deosai. Stop at Satpara Lake on the way. Enjoy the whole day in Deosai and camp at Sheosar Lake for night stay. (if u dont want to stay at Deosai, cross the area and reach Astore for night stay.
Day 5: If u stayed a night at Sheosar, today have more fun and chill at Deosai and then move to Astore. Night stay at Astore.
Day 6: Get a jeep to visit Rama Valley and Rama Lake. U may require to trek for 30-40 minutes to reach Rama Lake. Be back to Astore before afternoon. Get on the public transport and reach Gilgit. Night stay at Gilgit.
Day 7: Go to Naltar on public transport or hired jeep. On reaching Naltar, get some jeep (if u had gone by public transport to Naltar) to visit till Naltar Lakes. be back to Gilgit for Night stay.
Day 8: Hire some jeep or car till Naran. U need to start early in the morning, so better to make some deal with driver on previous evening. Reach Naran by Noon. Stop at Babusar Top and Lulusar Lake on the way. From Naran, get on some public tranport and reach Rawalpindi late in the night.
Note: It is just a suggested plan. U can always improve or change it as per your convenience and priorities.