How chose bank for program change?

Hi, I created an app that send program change on a virtual midi port.
The problem is that I can’t find the way to change the bank in which sending this midi message (many softwares, as mainStage, change scenes through program change but also recognise the bank in which program change is sent and for example to control this through my Keyboard Studiologic-Sl88Grand I need to change my LSB parameter to achieve this).

How can I solve this?

Thankyou in advice.

Program changes are not sent to a specific bank, they are send to change the sound of whatever bank happen to be selected at the moment. Sending a program change 26 e.g will select some sort of electric guitar if general midi is used. In one bank this might be sampled Les Paul, in another a stratocaster. The bank is changed with a CC bank select massage

Thank you for your reply! so I can achieve my purpose?
in attachment I’m putting an image that shows that mainStage for each Patch gives me a “bank select” that, as I said before, I control through my Keyboard Studiologic-Sl88Grand changing LSB parameter (when LSB parameter fits the patch of main stage is selected, according to the program change, while if LSB parameter doesn’t fit, even if the program change fits, the patch isn’t selected)?

Thank You Again!