Permalinks and 404 page

I have changed permalinks on my post (i have 1 post and 2 pages only) i am still getting 404 page.
i don’t use .htaccess i panic when i see filing and numbers and symbols i don’t understand!
i used permalink migration plugin but it didn’t work, it did work on the permalinks for one page before i did the post!
no no matter what i do i am still getting the 404
i have problem naming those pages and putting the right permalink!
i will be building about 100 content pages do i have to use permalinks on all of them?
please i need help step by step on this and i already moved my site from officelive.com to justhost and i didn’t move the starter pages (i didn’t know how!) so i started new ones but i am still seeing the old pages with another 404 page.
help please
thank you