Texting with Wi-Fi on iPhone 5s?

I just got a iPhone 5s (ios 10), and I won't be having service on it, just Wi-Fi. I want to use iMessage, but when I asked other iPhone users, I can text on iMessage with Wi-Fi, but only with iPhone users. The majority of people I usually text are android users, and I would like to text them on iMessage. Is there any way I can do that?

All help and suggestions will be appreciated!

Added (1). @Coffee: Do I need service or anything to do that? I'm very new to the Apple game, and i'm just finding out the vast knowledge from googling it and asking my cousin (who sold me this iPhone).

Why doesn't my laptop recognize my iPhone 4? - 1

When I connect my iPhone 4 (version 7.1.2) to my laptop (windows 7 ultimate) it makes the sound as if it's connected but the iPhone doesn't appear on my computer or on iTunes, and even the screen that mainly asks to import pictures doesn't appear! I tried all of the following:
*Restarting both iPhone and laptop
*uninstalling and re-installing iTunes
*Restarting AMDS from "services"
*using different USB drives and cables
*and I even had to reset my iPhone: and#92;
but nothing ever worked!
note: my iPhone worked absolutely well on my bro's laptop.
anybody please help:3

IPhone 5S to iPhone 7 Straight Talk transfer?

I currently have a iPhone 5S on Straight Talk service and want to upgrade to a iPhone 7 but they only carry 32GB I want the 128GB if I purchase a Unlocked iPhone would I be able to transfer my service with their "Bring Your Own Phone" program?

What to do if I lost my iPhone?

I lost my iPhone 5s this morning(probably dropped it when leaving my car)

What should I do? I tried locating it through icloud, but it says my devices are down so I probably put it on airplane mode.

Any advice/help will be greatly appreciated.