See the solution in explanation below.
Explanation:

You want to place these technologies to reduce attack surface and enable secure protocols for the web architecture.
Suggested placements (following typical best practices for web architectures):
First node after Internet (Inbound Traffic Point):
FirewallControls and filters incoming traffic from the internet to block unwanted access.
Next node (Internal Traffic Control):
RouterRoutes packets inside the network and can apply some filtering.
Next layer (Between router and web infrastructure):
WAF (Web Application Firewall)Protects web servers from attacks like XSS, SQL injection, CSRF, directory traversal by inspecting HTTP/HTTPS traffic.
Web Servers:
Web serverHosts the application.
PKI Certificate:
Applied on the web server or WAF to enable HTTPS and secure protocols (TLS).
Part 2:
