Thinking about getting a a37 5g phone for $40 from metro & porting my vz visible number. Then switching to tmobile's $15 plan. Will it be a smooth process?

I like visible but the extras, I barely use. I'm using wifi 98% of the month. And that 2%, I barely use up 2gb lol. And I never use hotspot. Compared to tmobile's $15 plan, i'm wasting 10 a month basically.

If I port my number, can get the a35 for $40. But i'm wondering, could I change to tmobile's $15 the month after?

Was thinking about getting a Lyca mobile account/number($7) but unsure how long it'd take porting out. Because i'd want to right after creating account. Basically i'm wanting the A37 as a spare but, it seems alot less headache if I just port my actual number & start maining it. Its $75 more($115) if I want a new number in the metro a37 promotion