afaik the only way to request to leave or begin the process is getting touch with site staff either thru email or maybe the discord (ive only ever known of one other user to do this)
but this sounds lke pretty average earnings given the main ways you're getting money are either ad revenue which acrues based on how many views your work gets and direct tips with ink/coins or whatever tapas' currency is referred to as nowadays which can net you a lot more than just ad rev/views
if you're certain you don't want to try it for longer then yeah i don't see any harm in leaving the program but if you're just starting out and willing to stick things out a bit longer then maybe give it another go
you'll obviously earn a lot more from separate funding platforms like ko-fi, patreon, buy me a coffee and the like but for in site earning programs thats just how it goes
at one point there were a few folks who'd actively track how much people were earning based on certain view counts tho I'm not sure how easy it'd be to find them now. it is still very likely that amounts that can be earned have changed drastically compared to the earlier days but if you're cool with a little pocket money at a time building up passively it's not too bad (speaking as a bit of a tapas oldie)
still whichever choice you make i wish you th best of luck with your work 