Q: Flashing symbols at startup: apple logo, circle with slash, folder with question mark

I have been trying to delete personal files off my MacBook (late 2008) to trade in. During this process the computer lost some function when deleting some documents; would not open apps but app would bounce constantly once selected and would not restart or shut down, had to manually hold down power button to power down.

When I turned it back on after a few minutes a blue startup screen came up as normal then Apple symbol but then started flashing to a circle with slash back to Apple back to circle then to folder with question mark. This continued for over 45 minutes + and has anytime I try to manually power down and restart.

I have tried the following:

- Try to get to disk utility by holding Command + R at startup

- unplugged charger and taken the battery out and put back in

- held shift while symbols are flashing

I can't check what OS I'm currently using but specs I do have for the computer are as follows:

- Computer is late 2008 model MacBook 13 inch

-  Model: A 1278 (EMC 2254)

- Storage: 160 GB

- RAM: 4 GB

- Processor: Core 2 Duo 2.0 13

Looking for any help to fix this issue. Thanks in advance.