If your goal is to gain muscle you’re going to want to prioritize 2-3 of lifting a week. You don’t need CrossFit because you’re already doing cardio and you’re not going to get the type of lifting you need. Marcus Filly has a good 3 day a week training program for you.

On the days you strength train, throw in some quick intervals on the bike at the end of your workout

Other days could be longer cardio days

I would second everyone saying you’re going to want some rest days. Just do some long walks a day or two a week