Disclaimer: I've stopped playing prior to 9.1.5, so if any of the below info is incorrect I hope someone corrects me
Renown: Since 9.1.5 they've made it even easier to catch up. Seeing as you probably want to get rank 6 legendary anyway, running Torghast will kill two birds with one stone by getting you renown and soul ash + cinders. Callings, world bosses, dungeons etc all give renown too so getting to 57 (I think this is the renown needed to unlock the last soulbind trait) should be reasonably fast. Anything after that is just a bonus (57 to 80 empowers your conduits and traits but for normal raiding and m10's, I'll assume they're not strictly needed).
Soulbinds: It depends which covenant and class you are. For example Pelagos is the best all around soulbind for a Kyrian sub rogue as far as I'm aware, which is the first soulbind unlocked. If one of the other 2 are better (WoWHead and Icy-Veins are common places to look at what is decent for each class and spec, along with class discords), you'll want to finish the covenant campaign to unlock them (which will also give renown).
Conduits: Doing callings gets you these pretty fast, along with chance to get them from World Quests, dungeons and Korthia too of course.
Gear: Korthia is your friend here. You can buy ilvl 200 gear from there with stygia, which you can upgrade 6 times. To upgrade you need to level Archivist rep and use their currency (forgot the name), and before 9.1.5 this was slow, but I believe now that it's quite a lot faster. Running m0 dungeons will also net you gear as well of course, but korthia is probably a good place to start.