Need help for sharepoint permision

• To add permissions to a list on a SharePoint site, follow these steps:
  1. Access the list to which you want to add permissions.
  2. On the top bar of the list, click Settings.
  3. Click List Settings (Document Library Settings or Survey Settings).
  4. Click Permissions for this List.
  
  Note By default, lists inherit permissions from their parent. If that is the case, you only see an Actions button that enables you edit the permissions of the parent or to edit the permissions of the list. This action breaks inheritance and enables you to grant specific permissions to this list only.
• To add permissions to a SharePoint site, follow these steps:
  1. Access the site to which you want to add permissions.
  2. Click Site Actions, and then click Site Settings.
  3. Select People and Groups if you want to add a user to a SharePoint group. Or, select Advanced Permissions if you want to apply explicit permissions.
  4. Click new, and then enter the user name.
  5. Select the appropriate SharePoint group or permission level, and then click OK.
  Note Sites that are a sub-site of a root can also inherit permissions from their parent. If this is the case, you have the option to break inheritance and grant specific permissions to this site only.

i hope this helps!