I need to know whether my sites is related to user profiles or not. Will we face any difficulties without using my sites? I referred this link https://technet.microsoft.com/en-us/library/ff382643.aspx for overview of My sites, but I need more Clarification about my sites.
You can setup the User profile without MySites, but still you need mysite host.
MySites are the User's personal Site collection where they can store documents, create list etc.
MySite Host is the Root Level Site collection with MySite Host Template. You need mysite host in order to User profile work properly.
- MYsite Host required for User profile pictures, as photo saved on the Mysite host's user profile picture library.
- People search also need the MySite host.
So, You can create a site collection with MySite host template, Use that as mysite host location in your UPA's settings. You should disable self service site creation so that no user can create their mysite.
MySites are using the UserProfile Service. You can't use MySites without UPS, however you can use the UPS without configuring MySites.
For further information the answer to this question pretty much says everything: