Thank you! Survival Mode is not yet in the game. However, as a new player, this won't be the mode for you. The idea is that cards used in this mode get a cooldown whenever they die.

Btw, if you plan to start playing you can start right now. It's free to play and start earning Glint which can be used to get soulbound reward cards. Eventually you can buy the spellbook to get more access.