steam app problems

i couldn't get into any of my games in my steam app and have to reinstall the app to play them do the app go bad.

Sometimes the app has to update itself.
If you're using Windows 10, there was an issue
with Windows 10 discussed ***here***
There was a firewall issue discussed at ***Steam forums***

window 8 is what i am using, and my firewall is window defender.

Windows Defender is what Windows 8 calls the Microsoft antivirus. I haven't found any forum threads from 2016 saying there is a problem between Windows 8 and the Steam client, though there are many from 2013, 2014, and earlier.

You might see if the information here works, even though it's from 2014 -- verifying the integrity of the game cache...
https://steamcommunity.com/app/295270/discussions/0/619569341117066262/

thank you very much.