Proficient means you add proficiency bonus to the check. Disadvantage means you roll twice and take the lower value. The 2 don't interfere with eachother.
A stealth check is a dexterity check (so, if your Dexterity is 14, it's a d20 roll plus your +2 modifier from Dexterity 14).
If you character is proficient in stealth, you can add your proficiency bonus to that check as well. For a first level character that is a +2 Proficiency Bonus, which scales up with higher level characters all the way up to +6.
If you have disadvantage on a check, you roll 2 d20's, and use the lower result. It does not change what modifiers (dexterity bonus, proficiency bonus) that you are allowed to add to the roll.
New player, trying to determine a stealth check for this character
Half-orc Fighter/Hexblade with Criminal back ground who is wearing Full-plate (getting Disadvantage on Stealth) but is proficient is Stealth.
How would I calculate the Stealth check? or do the two negate each other?
You still get your proficiency bonus to stealth. You just make the check with disadvantage.
"Not all those who wander are lost"
Proficient means you add proficiency bonus to the check. Disadvantage means you roll twice and take the lower value. The 2 don't interfere with eachother.
As others have said. For example, your stealth roll would be +dex +proficiency but you'd roll two d20s and use the lower roll.
dndbeyond.com forum tags
I'm going to make this way harder than it needs to be.
Thank you, All, for the clarification.