What about my recessed lighting or “cans”? Does the insulation go on top of them?

Cans or recessed lights are rated by the manufacturer as IC or non-IC rated. IC stands for Insulation Contact. You will want to confirm by checking the individual light fixtures before starting your project. These too can be sieves for air leakage. A best practice would be to air seal the cans and move insulation around the cans – not over them.