Broadlink RM mini 3 config

Hey, just wondering if anyone could help and point me in the correct direction…
I have got my Broadlink mini set up on home assistant, I have managed to get a simple volume up and down to work, so I can transfer that to HomeKit and tell Siri to then turn my tv up and down…
My question is Im wanting to tell Siri to turn let’s say ITV channel on, which will be multiple IR packets… as I need to press 103. I have all my IR packets 0-9 for the channels… but where do I start with coding it…
thanks in advance.