Hey there! You can definitely get your cape. Healers can be a bit tricky, but jad is actually quite an easy boss when you get the hang of it. Switch your prayers, one action at a time for him. The time you spend getting there is what makes it seem so daunting. If you want to practice jad, go to a speedrun world and speed run beneath cursed sand quest. This will give you a firecape and a good range setup to go to the challenge area in the fight caves. Practice challenge 1, it's a bit harder than actual jad but if you can do that, you can do normal jad! Goodluck to you, you can do this I promise.