I like seeing new people interested in soloing again once in a while, personally my own reason for soloing content is also the challange, combined with people saying ‘I bet you cant do this’.
If you want to start trying things out, I think you should really try and figure it out by yourself, find your own playstyle and see what weapons or traits you feel good using.
If you want to practice the basics of combat mechanics and dodging, I reccommend the cliffside fractal, look for the fractal, go solo the first boss, he’s got fairly straightforward but deadly attacks, its a great place to practice the basics of dodging, keeping focus and reacting quickly. Beat him on lvl 1? go to lvl 10, beat him there? lvl 20
Soloing things in general is about setting a goal, practicing and adapting,
1.go find yourself a place which you’d like to solo, I usually look for things that havent been done before.
2. Try it, see where you fail, see where you’re doing well.
3. reflect on the previously collected data, having trouble with condis? change to more condi removal, having trouble with projectiles? focus more on projectile deflection, having trouble with big groups? find a way to seperate them or practice using a more aoe based weapon.
This may not be exactly what you asked for, but to be honest, in a solo environment the dungeons are so varied thakittens hard to give any specific order to them in terms of, start here, end there.
