Dumb questions regarding manual account setup

yo. so im interested in getting a basic new device and setting up Altice mobile 1 gb per month data for $12 per month. i want to setup a system where im manually creating emails and IG accounts connected to those emails (i may even just buy bulk emails). if i create accounts this way, what problems will i run into? can i factory reset the phone every 10-20 created accounts to continue creating? i’m not looking to replace purchased accounts, just supplement.