UPDATE 8/30/2021
So i ordered a 7 days free trial of mint mobile from amazon (0.99$ for sim card, sim tool, and activation code). I was unable to activate the sim on the LEM14 BUT once i activated on a cell phone/sim swap (Sammy S21) I was able to install the sim card in the LEM14 and it worked for data/phone/text… on day 3 of trial and I’m pretty happy. free trial comes with 250 min, 250 txt, 250 mb data. I might continue once this expires. Heres a link to what I got:
I ordered my LEM14 from Banggood and I’m looking for a reasonably priced nano sim; my plan is to use it on the LEM14 and then once I’m over my new toy ill put the card into an old s9 edge for my son to use (he’s only 6 but I’m tired of him stealing my phone to watch other people play minecraft while I’m driving 
) mint seems cheap for unlimited at 90$ for 3 months unlimited but I want to make sure it will work and I don’t know about compatibility. What are others using for sims? vender, plan, cost. thanks-Adam