Do you have to have a downloadable copy of the game or can I like upload it to kongeregate or something (construct 2 needs to pay to download), do you have any good engines to use(not too complicated but not too simple)?
Once you are done make a playable demo of your game - head to the Retro Plaftormer Jame home page and hit the "Submit Your Project". Note:This link will only appear once the Jam has started.
Hitting on that link will take you to a Submission prompt
Hit the "Upload game", and create your new project. More info on uploading your First Project https://itch.io/docs/creators/getting-started
As for Game IDEs , here's a list of free and paid services, some easier than the other
Godot Engine https://godotengine.org/
Construct 3 https://editor.construct.net/
Amazon Lumberyard https://aws.amazon.com/lumberyard/
GameMaker Studio https://www.yoyogames.com/gamemaker
RPG Maker http://www.rpgmakerweb.com/
Isogenic Game Engine http://www.isogenicengine.com/