Hi Himanshu,
You need to use maintenance plan category only for Notification.
Create a Single Cycle Plan, with cycle / unit -7 days.
On scheduling you need to set the start day when you want to start like Tuesday, similarly system will schedule the calls every week based on the scheduling period you have chosen (6mon,1 year etc)
For Multiple Equipment, if you want to have the Notification generated, then you create maintenance items.
If you want to include in one order, then in the maintenance item you assign the object list.
Regards
Terence