Yes, for for first timer it’s hard to choose which devotion to pick, I remember I was overwhelmed when playing my first character on choosing which skill to use or devotion to get. In the end I’m just following others build to follow their devotion route.
My tips on choosing devotion is to know which damage you want to use. For example, I’m gonna play a Pierce Blademaster with Cadence as main skill. With that in mind there is 3 things I want from devotion: Resist reduction, sustain, and T3 damage constellation.
For getting a pierce RR, I’m gonna take Assassin Blade and max it node first to get the skill, then for sustain people said that ghoul proc is very useful in melee with it massive life leech, so I’m taking that next. Now my next target is T3 Pierce Damage constellation, there are 2 constellation that support Pierce damage: Azrakaa and Unknown soldier, so I getting the constellation that fulfill the requirement for either of those T3 constellation. I choose them by this order OA/DA, pierce damage/all damage, adcth, health/armor. Thankfully, Azrakaa and Unknown Soldier has similar requirement, so If I’m spending my devo point well, I might get them both (for other type of damage it will be harder). In the end here is the devotion that I pick: https://www.grimtools.com/calc/d2jywx4N