Experience points aka XP are essential in Respawnables in leveling up. By leveling up, you will get to unlock new and more powerful weapons and equipments to help you in your match.
You gain Experience Points (XP) by finishing Matches (Mission and/or Multiplayer), by completing Missions , by buying either of the XP boosters (small, and medium), and by defeating Elite Bots that drop XP boosters. The higher your match end position, the higher the XP rewarded.
Multiplayer matches will reward player with more XP than Single Player ones.
When you reach the level cap (level 50), you cannot gain any more XP. Additionally, you can get double XP by using Boosters, despite not earning anymore.