Which Prepaid plan? Simply Prepaid: There's a $5/mo add-on you need. T-Mobile ONE prepaid, you're good. BUT be aware that the cost to make a call in Cypress is $2.99/min. I'd forward all calls to voicemail. If you want to make calls home, put phone in airplane mode, turn WiFi back on and use WiFi Calling.
Manage your T-Mobile account