Well, with your $500 budge cap, that will get you a GREAT "mid-high" level gun, but no gear... Airsoft is really a sport where you should jump in with $750+. My first rifle alone was JUST under $1000.
First things first, you will need to get AV'd so you can get access to our classifieds and retailers section. There are the weapons your interested in both new and used in there.
The type of rifle does not really matter, its personal preference, what does matter is who made it. The rifles you are looking at are made by a WIDE variety of manufactures. I only have personal experience with CA, TM, and KJW/TK, so I can only say that CA is probably your best option for your price range if you buy from the right retailer or find a good deal in the used department.
Welcome to the forum, have fun, stay safe and good luck!
Please take some time to read all of the FAQs in the FAQ section, there is VERY important information there for you, including information on how to get Age Verified.
Also included in the FAQs is information about what NOT to buy from outside Canada - I suggest this be one of your first reads.
One thing you will find on ASC is that we are not here to spoonfeed you. Please show some initiative and research topics on your own, pretty much any question you can think of has been asked before, so please use the search function up top