Confused FTM - milestones

Helppppp my baby turns 3 months old in a week and I am feeling so lost on when milestones should happen and when I should be doing certain things like transition out of swaddles, etc. I saw a post say 15 weeks start transitioning out of a swaddle and it just made me think I don’t know any of this! He’s doing great and FINALLY is sleeping longer stretches at night. He’s lifting his head all the time so I think he’s on track but as he gets older I want to make sure I have the right learning toys, etc.

Are there any apps or books you’d recommend that are just informative (not how to parent)?? I have the wonder years app but it’s just about leaps.

Thanks for the help! :)