I have some problems in compressing anything,it not become smaller file size. I am using window 10,7 zip ,compression level-Ultra,etc..shown in web. But it compressed only little smaller size .eg I made 100Mb, it became 99Mb size. Please help me in knowledge.
Data can't be compressed infinitely. In particular, data that is already compressed doesn't compress well. Otherwise we could compress, then compress again, then repeat and so on, getting smaller file each time. It's not possible due to information entropy. There's some amount of information in each file that has to be stored if you want to recover original file without any malformations. Compression is basically about storing this information in optimized way. Optimized stuff is already optimized, you can't optimize it again to get better results.
Movies, music and software installers are usually already compressed, so they don't compress well.