Two considerations for preventing users from accessing Salesforce from outside of their network are:
IP address restrictions are set on the profile or globally for the org, which limit login access based on IP ranges specified by an administrator Restrict U2F Security Keys on the user's profile to enforce login hours, which require users to use security keys during certain hours of day Assigning single sign-on to a permission set or enforcing Login IP Ranges on Every Request will not prevent users from accessing Salesforce from outside of their network. Reference: https://help.salesforce.com/s/articleView?id=sf.security_networkaccess.htm&type=5 https://help.salesforce.com/s/articleView?id=sf.security_keys_restrict.htm&type=5

Account and contact are two records that can be created when using the lead conversion process. The lead conversion process converts a lead into an account, a contact, and optionally, an opportunity. Reference: https://help.salesforce.com/s/articleView?id=sf.convert_lead.htm&type=5

To use as an identifier when importing and updating records from a separate system, an administrator should use External ID field type on an object. External ID fields allow storing unique identifiers from external systems and using them for matching records during import or update operations. External ID fields can also be used for upsert operations that insert new records or update existing ones based on external ID values. For example, an administrator can create an External ID field on Account object that stores account numbers from an external ERP system and use it for importing or updating accounts from that system. Rich Text field, Record ID, and Auto-Number field are not suitable for using as identifiers when importing and updating records from a separate system. Reference: https://help.salesforce.com/s/articleView?id=sf.fields_about_field_types.htm&type=5 https://help.salesforce.com/s/articleView?id=sf.data_loader_upsert.htm&type=5

To surface important values based on the stage of the opportunity, the administrator should use path key fields that display fields relevant to each stage along with guidance for success. Path key fields can be customized for each stage and can help users focus on key information and actions as they move opportunities through the sales process. Dynamic forms, opportunity processes, and workflow rules are not designed to show values based on stages. Reference: https://help.salesforce.com/s/articleView?id=sf.path_key_fields.htm&type=5

Knowledge is a feature that can be used to meet this requirement. Knowledge allows users to create, manage, and share articles that provide information and solutions for common issues or questions. Data categories can be used to organize articles into different topics and make them easier to find and access. Users can view related articles from the Case page layout based on the data category of the case. Reference: https://help.salesforce.com/s/articleView?id=sf.knowledge_overview.htm&type=5 https://help.salesforce.com/s/articleView?id=sf.knowledge_categories.htm&type=5