首先，检查您的VPC和该VPC中创建实例的子网.该子网将具有一个路由表，请验证该子网是否已连接到目的地为0.0.0.0/0的Internet网关，否则请通过引用

First of all, check you VPC and subnets inside this VPC in which you have created your instance. The subnet will have a route table, verify that subnet is attached to an Internet Gateway with Destination 0.0.0.0/0, otherwise add one by referring this link. Post this step, check that your security group has an Ingress Rule for port 22 from your ip(select my ip from drop down). You will not get Connection timeout error if these two steps are configured properly.