@Herby48 The routine for this kind of age is more of a cycle, rather than anything by the clock.
If you want to encourage independent sleep, now is a good age to get baby going to sleep where they stay asleep. This is more easily done in something that moves so that you can "rock" baby in that, rather than in your arms.
Speaking as a mum of 4 (and with only 14 months between my eldest two), I would recommend naps for baby in a bouncy chair. It means you can put baby in there after their awake window, then sit on the sofa playing with your toddler while bouncing baby with your foot.
Naps in a pram work in a similar way, but are not hands-free since you'll have to push the pram back and forth so that makes occupying your toddler more difficult.
If going for naps in something static, you'll need a lot of extra reassurance tactics to get good sleep. I'd recommend a tight swaddle and dummy to help baby settle. You may also need to do some patting and shushing, so again not as hands-free and toddler-sibling-friendly as a bouncy chair.
A dummy will make all of these independent sleep methods easier. And without any crying. Dummies are ACE for independent sleep.
Your "routine" wants to be repeating cycles, according to a predictable awake time window. In this under 12 week old age your awake time window wants to be 30-60 minutes maximum:
Wake (mentally note the time and work out when awake window will end) > Feed > Awake time on floor having a kick around > At awake window or before if any crying or clinginess starts > top up feed if needed > Into bouncer and relentlessly bounce at even tempo until asleep > Wake.... repeat over and over again.