How to do loop

Hey everyone,i just start with wordpress and i like how it works,but i have one question and i hope that someone can help me.And i am sorry if my english is not good enough.

– When i use some random theme i wana make my home page static with one post.That means i need loop that show only one post(first or first 3for example) on home page and then others posts to go on some random page-POSTS.Its very important to be first post so content of home page dont change if i make another one.Something like in index i need “if posts then echo first one and then stop, and then on page.php loop that say if posts echo start from post2 “.I hope that you undestand me.

Thanks.