'I saw on the latest Firefox webpage advising us of updates that Firefox now has a free, 50 GB/mth, VPN. However the VPN button doesn't appear in my browser, even in the More Tools and Customize Toolbar options. Is this feature not yet available in certain countries? I would like to use it.'

Patience, Grasshopper; patience. The free limited VPN is most certainly NOT available in many countries. That info is provided more than once in its description. Imagine, from a business point of view, what would happen if Mozilla offered a free VPN to the world. Infinite demand. VPN resources have to be paid for, so any business would 'test the water' before expanding any new offering. Yes? So just wait.