Opposed Rolls
There are no Opposed Rolls. See e.g. https://www.reddit.com/r/dndnext/comments/1ivv141/why_have_contests_changed_in_the_2024_edition_of/. I can't include the rules here because they are not in SRD 5.2.1 and thus they are not under CC-BY-4.0 license. (errata SRD 5.2.1)
See also Unarmed Strike (DC for escape attempts equals 8 plus your Strength modifier and Proficiency Bonus), Hide action (Make note of your check's total, which is the DC for a creature to find you with a Wisdom (Perception) check), and Variant Rules.