How do I prevent all players from editing/breaking/building anything in my mcpe server?

*Asking this again because the first time nobody answered…*

So I've built this HUGE world in minecraft pocket edition that took me a year to fill and want to turn it into a server. Most servers I see are for people to build things in but for mine I just want people to view and explore it because I've already built everything. I can pay for server hosting if necessary but does anyone know of a setting anywhere or something I could do that'll lock all the blocks (not just in specific areas) to avoid it being griefed or destroyed? I don't want to have to constantly maintain or worry about it…

Do /gamemode a (insert player name)

Set the server's default gamemode to 'Adventure'. Players can open doors, use levers & button and interact with mobs, they can't break blocks

Once you've converted the PE world to the PC format (normal server)
Find the world's 'level.dat' file, open it and find "gametype", set the value to "2" (adventure)