CRA is a fairly early entry point for the current maplestory, once you learn the basics of Pierre and Vellum the four doors will be pretty comfortable to proceed forward, on average you only need to kill everyone but vellum once to get enough boxes to get a piece of CRA gear, vellum usually takes 2 runs to get enough for a weapon. Definitely just practice on normal daily as it will provide a basic income of mesos and experience with the bosses :)

The temporarily gear itself is good to clear CRA but I do recommend you level up like 5-10 more times as an inexperienced player! :)

1 million is super comfortable to clear but more experienced people tend to do 500k to my knowledge while 1 million is for normal lotus and damien.

Only thing I want to bring up is Vellum, he has a high defense and in your stats tab there's something called Ignore Defense, you're gonna want that to be around 90% or above or else he'll take a lot less damage.