How can I keep US phone number primarily for banking and 2FA purposes but also have (i) ability to text/call US from Mexico and (ii) get data for internet access? I'm so close to throwing my phone in the toilet...

I swear the more I read about this frequently discussed issue, the less I understand it. Ugh. My circumstances:

• Have longtime US number and Boost Mobile is provider
• Already in Mexico, so I think this limits my ability to set up GoogleVoice or other voip service that will reliably handle 2FA requests
• Have Samsung Galaxy A25 phone that allows 2 SIM cards but not eSIM
• Want to keep current US number for 2FA but also bc every business and personal contact I've ever had only knows that US number
• Have wifi access but need sufficient data for average internet use when wifi not available
• I dont think I need a mexican phone number as I always use WhatsApp, but idk
• I'm in Cuernavaca, Morelos area
• Bc I bought phone from Boost 9 Mos ago they claim they cant/won't unluck number until 3 Mos from now, seemingly limiting my ability to move US number to a different provider

THAT'S A LOT OF INFORMATION AND I'M LOSING MY MIND!

Get a new US phone number from Telli via SIM card solely for 2FA purposes (5 USD/mo)? Get Boost to unlock phone and transfer to Mint for continuity of US number (15 USD/mo)? Err... source for data? Give up and pay AT&T 70 USD/mo?

If anyone can help me figure this out I'll wash your car, dog, or feet (whichever is the least foul).