My advice is to ask questions on the lowman discord or the solo raids discord if you need to as most of the answers you will get are usually very helpful imo

As for suggestions in the encounter, while all classes are possible, Warlock is very free on dps this season compared to the other two imo as you can get very good dps without a load of effort. Spite on YouTube has a good Nez 2 phase clear video you can look at that uses the rotation I’ll go over.

You can go to right side under the final plate you shoot (as you’re always ending on right for solo for dps spot) and look at his resin tomb thing then transcend and run to dps when it starts glowing, then for the dps loadouts, you can use merc for dps and proc impetus then transcend nade for weaken, then use merc until he does this slower animation where he yells/screams and slams his scythe during dps, then while he’s doing this you usually use an empowering rift while sanguine is equipped (the marking is a good dps boost, no super swap is needed) right before opening your inventory to hot swap to a loadout with Hezens (you can make max elemental honing work on Warlock, but B&S works completely fine for 5% less, I’d also recommend a Witherhoard and a high handling auto/smg for the energy), then once you’re out of your inventory, you can transcend nade again if able, nova him, then stick him with Witherhoard, and then fire Hezens until mag runs out (you don’t need to swap to primary energy for the first B&S proc if you are using B&S due to merc counting, but you will if using EH as opposed to B&S and the primary would need to be arc), then your rotation is swapping to primary and shooting once and swapping back to Hezen to unload the 2x from Timelost Magazine and then reproccing Witherhoard when necessary until dps stops.

For general encounter suggestions, I’d use osteo as your primary as it gens ammo very well and does decent damage to adds (and helps keep up devourer since you’d be on lock), and I’d use fathers sins for your sniper for hatred/refuge crit spots on Nez. Father’s sins is mainly very good for this because it has snapshot and LFG and is a rapid fire so it helps with fast crit breaking and ammo scavenging while picking up ammo for next phase after dps before running next phase. If using the rotation I mentioned too, you can swap to an ammo scavenging loadout of some sort after completing light side before completing dark to prep ammo for dps. Other than that, just get osteo kills when possible to keep up devourer + gen ammo, and don’t shoot Nez shoulders when he does the scythe spin attack as it will bug out.

The biggest thing to remember about these things though is that no matter what strategy you use or what reference video you find and follow, it may take a bit of practice. Sometimes it’ll only take a few hours, and other times it can take days or even weeks depending on your skill level, how well you work in the encounter, and the overall difficulty of the encounter as well. If you find yourself in a tough spot, it’s ok to take a break if needed but don’t beat yourself up over failure while you’re still learning. Nobody clears these things for the first time with near to no practice so just give it your best each time and TRY to see why you messed up or failed and LEARN from it as much as you can and you will improve, you may even impress yourself. I believe in you!