I am doing a project where I want to make several users to have their own page.
User:guest1 has his own page in sharepoint
Users:guest2 has his own page in sharepoint
should i use site pages? or what should i do?
I would recommend you have webparts that are geared around user groups. rather than a seperate page for each group of users. So the webpart will show/hide depending on the group.
if you insist you can have a webpart that finds the group that the user is in and redirects to a page that only that group has access to.
either way you will need a webpart and groups that users are in. Creating a page is simple on the site. Just create a webpart page will be sufficent :) , if your looking for individual page for each user than the first option is best as each page will show the webpart or/and info that is related to that user on one page for all users :)
from the examples above you can do what your looking for easily :)
At central administration go to Web Applications. Select a web app and in the ribbon there will be "Self-Service Site Creation". Then select the options however you want. If I understand your question right, it has to solve your problem.