Using Azure Application Gateway to provide secured access to your published applications or services in Azure.
Using Azure Firewall to protect your Azure environment.
Using Azure NAT Gateway to provide your Azure Resources with internet access.
Using Azure Bastion to access Azure Virtual Machine resources.
Here is a high level guide to connected your on-prem envronment to azure using Site-To-Site VPN
Designing Azure Network infrastructure with HA and Security can be difficult, here are some basics to consider.
Azure Network Watcher is a service that enables you to monitor and diagnose conditions at a network scenario level
Azure Network Watcher is a service that enables you to monitor and diagnose conditions at a network scenario level
Learning the fundamentals of Azure Virtual Networking
Monitor your Azure resources using Azure Monitor with DevOps and Tags for exceptions