Role hierarchy and sharing rules are two features that should be used to open up access to Opportunity records for sales users working on collaborative deals. Role hierarchy can be used to grant access to records owned by or shared with users who are below them in the hierarchy. Sharing rules can be used to extend sharing access to users in public groups, roles, or territories based on certain criteria, such as record owner or field value.
References: https://help.salesforce.com/s/articleView?id=sf.admin_sharing.htm&type=5https://help.salesforce.
com/s/articleView?id=sf.security_sharing_rules.htm&type=5