The ‘Secure’ attribute in cookies is a flag that can be set by the server when sending the cookie to the browser. When a cookie has the ‘Secure’ attribute, it means that the browser will only send the cookie back to the server if the connection is secure, typically over HTTPS.

To set cookie flagged secure open xampp control panel then click on cofig then select PHP(php ini) file

open php.ini file then search session.cookie_secure then replace this(;session.cookie_secure =)
replace this line with

session.cookie_secure = 1
remember remove(;)

Save file and restart apache server after that you found result cookie flagged secure

Note if cookie not flagged secure then clear cache or try on incognito mode
Also read this
- How to change TLS version in xampp apache ?
- How to disable HTTP TRACE/TRACK (TraceEnable) methods in xmpp APACHE
- How to set Cookie Flagged ‘Secure’ in xampp apache ?
- Turn of Server Signature in xampp apache ?
- How to configure Proxy server In xampp Apache
- How to set SameSite cookie in xampp apache server ?
- How to set a cookie with the http only & secure flag in PHP?