I want my dataset/collection to be completely custom for each person who uses the website. This way data someone else adds to the website would not appear in the collection or dynamic page of another user.
This is wrong, if you want to show specific data for a user (data that belongs to X user) you can use filtering with “_owner” field you shouldn’t create new collections for each user to just filter data based on user, it’s a bad db design and wrong way to filter data based on user.
You can filter data using .eq operator of wix-data. Learn more here.
Or if you are not coding and using visual elements to connect data to your page elements. You can use filtering with logged-in user and _owner field, in this way you can show content only that belongs to logged-in user.
If you want to do something else let me know. If my answer helped and was clear for you mark it as solution so everyone can see this topic as solved.