The way I made the thumbnail of my video was by uploading it to YouTube, and they gave me the option, I had to verify my details, but is pretty straight forward.
The video that made the final push to make my channel:
How Social Security Works CNBC • How Social Security Works
The channels I follow
(For investing and saving)
Graham Stephan / @grahamstephan
TLDR = Too Long Didn't Read
(For news on USA)
TLDR News US
/ @tldrnewsus
(For News on UK)
TLDR News UK
/ @tldrnews
They also have a channel for EU
(For investing explained)
The Plain Bagel
/ @theplainbagel