Newbie looking for guidance

I'm recently retired after more than 50 years in the computer industry. I've also published two SF novels, hence the user name. Also I have published some short fiction and a computer textbook. I have watched a few DnD games on video and think I'd like to try playing. In time I hope to work up to DM, but that will take a while. I've roughed out an idea for a campaign that I'd like to think I might run one day. If anyone would like to see it I'd be only too happy to share. I can bring to the table a lot of technical knowledge, a devious imagination and a sense of humour. For example I have an idea for a door that can only be opened by finding five things which have the word "key" in the description but are not keys, such as a key lime pie. I am a complete newbie to RPGs and would appreciate any advice.

Hi, it helps if you specifiy what time zone you are in, and what days and times you are available  to play. Are you looking for just a learn to play session, or a shot or long campaign?  With other players? Etc. I am a retired Navy Vet living in Thailand in GMT+7 working on my first and second Space Opera novels (that are both way behind schedule). Being that you write sf, I am surprised you are not lookjing for an SF RPG, like Traveller, or similar. Welcome to the site. Roll20 serves games around the world. 

Hiya. I can run 3.5 or 5e dnd interlinked one shots or short games if interested. I also teach the 3.5 and 5e system. Dm me if you need some help or want to play. I am udt -7.