Advice for Early-Midgame

Recently got into RL Craft through Union's videos but I have no idea of the progression of the mod and what items to go after. I thought I would go for the dragon eye like I saw in his videos but I didnt realise the recipe changed and now I dont have nearly enough resources for it. Currently I'm still using iron armour but do have a set of unenchanted diamond(I don't wear it often though since I dont want to lose it). Also I only have 2 extra hearts from mining. My levels aren't too great since I seem to never have a ton of experience to spend.

What should I do next at this stage or is there any particular items that would help?

(Sorry if this is a generic/low effort post)