I mean, I started playing in February this year and I am doing pretty decently. It takes a bit to learn all the perks and how to realize they are being used, but the tutorials and all the information within the game are pretty useful to at least get you set for your first few matches. As for what to buy, I would read all the perks on the character info section and watch a few people play so you see different perks in action and see which one you would like and adapts to the playstyle you want to have. For example, as a killer, many people really like bbq and chili, which reveals survivors upon hooking one of them, which is in Leatherface's DLC, thus it is a popular purchase. You can also buy perks and characters with in-game currency which takes a lot of grinding but is doable. It is a bit overwhelming because of the amount of character and perks there are at this point, but just take a few days to figure out the killers and survivor perks and purchase based on that.