To grow in strength you need to upgrade your equipment, the maximum armor upgrade level is 40 for each part. Only Celestial Set can reach this level. Each armor has its own upgrade cap and you can check it here → sets

Up to level +10 you can use Upgrade Stones or Catchup Stones. Acquired from monster essences, archlight crates, wild bosses, quests.

To upgrade your gear from +11 to +20 you have to use Legendary Stones. Acquired from monster essences, quests, sigils and transmuting upgrade stones or soul and rune soils.

To upgrade your gear from +21 to +30 you have to use Awakened Stones. Acquired from monster essences, quests, sigils and transmuting Legendary Stones.

To upgrade your gear from +31 to +40 you have to use Relic Stones. Acquired from monster essences, quests, sigils and transmuting Awakened Stones.

Healing Rune is is equipped next to the boots, and provides the main source of healing for most of the vocations. You start with the Beginners Emblem, this cannot be upgraded and is given to you upon character creation.
T2 Healing Rune can be obtained from Heroes Quests.
T3 Healing Rune can be obtained from the Seven Trials Quests.
T4 Healing Rune can be obtained for 750 Forgotten Gold.
T2 Soul Rune can be bought at Forgotten Island for 1250 Forgotten Gold.

Soul Rune is the main source of damage for most of the vocations. At the beginning of the Season you get a soul rune(classic) upon reaching lever 300. If you lose this, you can buy one from the rune seller NPC at depot floor +1, south east. Unlike the healing rune you can instantly upgrade your T1 Soul Rune upon receiving it.

Up to level +10 you can use Rune Soil/Soul Soils or Catchup Rune/Soul Stones. Acquired from monster essences, archlight crates, wild bosses, quests, ritual bags, legendary keys, heirloom crates and by breaking all type of higher stones at blacksmithing station. (Awakened & Relic).

From +10 to +15 you can use Awakened Rune/Awakened Soul stone. Acquired from monster essences, archlight crates, wild bosses, quests, ritual bags, legendary keys, heirloom crates and by breaking all type of higher stones at blacksmithing station. (Relic).

From +15 to +20 you can use Relic Rune/Relic Soul stone. Acquired from monster essences, archlight crates, wild bosses, quests, ritual bags, legendary keys, heirloom crates and by breaking all type of higher stones at blacksmithing station.

From +20 to +25 you can use Relic Rune/Relic Soul stone. Acquired from monster essences, archlight crates, wild bosses, quests, ritual bags, legendary keys, heirloom crates.
Available after you buy the rune enhancement token (Sold from Gustavo 1.5k Wargate currency) Have to use one on each rune/emblem.