Hi roberty10279373,
For Page Load Rule condition, if you want a condition to fire the rule on a specific page or a set of pages, you can look for path of the page to match. You can also utilize your Data Layer to define conditions. Ultimately, it your requirement on which these conditions will be configured and you can refer to the available options under the below article:
https://marketing.adobe.com/resources/help/en_US/sc/implement/dtm/t_rules-page-conditions.html
For Event Based rules, the task is to uniquely identify the element on which the action is being done. Hence, CSS Selectors is the best option here. If that doesn't work for you, you can use attributes in the element to uniquely identify it. Apart from this, many options are available to deliver you with ease to configure the rule, which you can refer in the below article:
https://marketing.adobe.com/resources/help/en_US/sc/implement/dtm/t_rules-event-conditions.html