です is used with noun and adjective, and ます is used with verb. は and が are subject particals in general. However, は can be used with some of other particles and が is sometimes used as an object particle. Besides, there is also に as an object particles. All are dipends on the sentence, situation, what you are taking about, etc. You should learn from the beginning, step by step. There are a lot of web pages to learn Japanese and here are some of them. http://www.guidetojapanese.org/learn/grammar https://www.nhk.or.jp/lesson/english/learn/list/ http://study.u-biq.org/english.html http://www.freejapaneselessons.com I hope you find some for your study. Good luck!