When you create a new user account in Salesforce, they receive a standard email by default. From Salesforce Spring ’25 Release, now you can configure a Customized Welcome Email to New Users from session settings.
You can set the amount of time that the verification link in the email is valid for 7 days, 1 day, or 180 days are your choices.

How to configure Welcome Email for Internal Users in Salesforce
This change applies to Lightning Experience and Salesforce Classic (not available in all orgs) in all editions.
Step 1: Create a Custom Email Template
Create a custom classic email template. To add the verification link, include the new {!NewUserWelcomeEmailLink}
merge field.

Step 2: Update New User Welcome Email Settings.
Update New User Welcome Email Settings from the Session setting. Setup->Session Setting

From the Session Settings page in Setup, add the email template in the Welcome Email Template field.
Step 3: Test Customized Welcome Email to New Users
Create a new user and check which email they get it.

Sign up for a pre-release org to see what you can find.
Summary
Check out “Salesforce Spring ‘25 Release Treasure Hunt!” session recording. In that interactive session, participants can embark on an exciting journey to uncover the latest features and enhancements of the Salesforce Spring ‘25 release. Daryl Moon checked the idea exchange, and look there at ideas that are under development and jump into a pre-release org that to find the Salesforce Spring ‘25 Treasure Hunt