When I'm trying to access my WordPress dashboard like, https://www.example.com/wp-admin then it automatically redirects to
https://www.example.com/wp-login.php?redirect_to=https%3A%2F%2Fexample.com%2Fwp-admin%2F&reauth=1
What I'm suppose to do?? and when I login to this url I'm redirect to example.com/user/
I'm not able to access WordPress dashboard
and when i enter username and password and try to login, it's redirect to user page
 
                        
It seems the problem in your
.htaccessfile. Please delete.htaccessfile and try to login again. Then logged-in successfully.After that, you can access your dashboard URL https://www.example.com/wp-admin.
Note: Now you need to change permalink from admin panel as:
Change to plain and save it. After visiting then you reset it and
.htaccessfile regenerate automatically.