The broken spell of Pass without trace 5e attack, work & stacking in dnd
Does an additional 10 Stealth bonus that comes with the Pass without Trace 5e spell added to the present Stealth reward?
Yes, passing without trace is a bonus to the character’s current Stealth test. The spell “pass without trace” description reads: A haze of silence and shadows erupts from you, obscuring you and your friends from being noticed. The duration is for 30 minutes. Every creature within 30 yards of you (including you) receives a bonus of 10 on dexterity (Stealth) checks. They are unable to be tracked unless by magic methods. A creature who receives this bonus doesn’t leave trails or other evidence of its travel.

The spell doesn’t state that it is replacing your existing Stealth check modifier. Therefore it’s an additional feature. Suppose two features in a game don’t have identical names. Their advantages are stacked on top of a basis. (In this scenario, there’s no way to have two different abilities or features being stacked; it’s one bonus that is stacked on top of the standard or existing bonus.) It’s not without limits.
It is important to note that the spell’s description states that it only adds an advantage to your Stealth checks and blocks the possibility of being traced later on. Still, it does not make your voice invisible, completely inaudible, unrecognizable (as Jeremy Crawford clarified on Twitter) or even impossible to spot with other senses.

Additionally, the spell’s description states that it will grant these benefits to those who are within 30 feet of the caster. Crawford clarified on Twitter that the spell is designed to help creatures only if they remain within 30 feet of the caster. However, the spellcaster can select different targets throughout the spell.

Suppose the enemy is on looking for the party. They need a place to cover themselves with; if they walk out in the open, enemies will be able to spot them, whether they use a spell or not. The party will keep away from the eye and adhere to the hidden rules, that’s right.