Lately when i start up my compyer ,it was very slow ,it take very long time to load finish all the program , i can't surf net , I scan my computer didn't detect any virus , acn any one help !!!!!

Are you sure your computer has enough ram? Also are you sure that when your shutting down the computer your doing it correctly with most of your apps closed? Another thing could be that you have downloaded to much stuff. Try doing a disk cleaner check to see if you can get rid of some stuff that you don't use to get some cpu usage back.

Try Running Malwarebytes Anti Malware And See If That Finds Anything!!!

Because If You Say Just Lately That Your Computer Is Acting Slow On Start Up, Then My Guess You Have Some Malware Or Some Other Thing On Your PC, But As BadMax Stated Could Be A Number Of Things Slowing Your PC Down, Make Sure You Have Enough Ram, Or Get A Registry Cleaner Program, Or Defrag Your System!! Leave Us Know How You Get On!!!

1.Download and install:
Absolute Startup Manager(optimizing system run)
2. Clean registry using CCleaner