You can only play in those if you are a verified titled player OTB.
So, the first step is get an OTB title. If you do have one, you have to get verified: https://support.chess.com/customer/en/portal/articles/1444932-does-chess-com-offer-benefits-for-elite-or-titled-players-
Please tell me how I can join to Title Tuesday and Death match.
Thanks!