yea if you can use both lines on your phone that is perfect. I had that ability also, until the phone died haha!

In most countries i have noticed you can either get a phone plan or just a sim and add money to it each month. Which is what everyone i know does. I personally just use wifi and when i leave the house have no phone. for me it works, but can be a challenge.

I use coinbase, but i have heard there are better wallets out there now. My brother uses Celsius, he likes it.

I am not an expert at bitcoin i bought it before it was sooo popular, and coinbase was the ONLY wallet!!

I do have some altcons on coinbase and on robinhood (not the best place to buy!).