How to grant a specific group of people access to a specific area of a Sharepoint Site

Make sure you have full admin access to the site.

1. Firstly, click on the cog icon in the top right-hand corner of the SharePoint site (just to the left of your account icon) and click on Site Permissions:
2. In the next window, click on "Advanced Permissions Settings", this allows you to view the permission groups.
3. In the perrmissions screen, click on Create Group:Input the name of the group, the group owner, and if you want enable to "Allow Requests to join/leave this group", it is not recommended you change the "Who can edit the membership of the group" option, below all of this you can choose the permissions, because we don't want them to have any permissions to the wider site, leave this blank, do not tick any of the boxes.
4. In the next window, click on new and then add in the members of the team.
5. After you have added the members, go back to the area you want to give people access to, and click on the same cog icon as before, but this time choose, Library or List settings. 
   Then click on "More Library Settings" or the alternative for a list
6. In the next screen, click on "Permissions for this Document Library"
7. Click on Grant permissions, and then type in the group name we made earlier, then click share.

Now, you can leave it there and the user will need to use a link to the specific list/library, or you can do a little bit extra below to allow them to browse and easily find the content they need.

1. To grant access to the home page. Click on Settings and then choose Site Contents, find the Site Pages option and then click the three dots and manage access.
   
2. Next click on Permissions for this Document Library
   
   
3. If the option appears, in the top left select Manage Parent
   
   
4. Now choose grant permissions, to add a group, type in the group name you made in sharepoint earlier, and then click show options, and then select the appropriate permission level.
   
   If you are adding a group into this area, then DO NOT choose a sharepoint group in the permission level, this will not work and it will come up with an error.