As a noob in AWS, I've been given a chance to try out AWS, I wanted to fire up a server but when there's a choice between these two EC2 or Lightsail, got me confused a bit but I found nice answer in stackoverflow, of course I tried EC2 but this lightsail just need to get my hands on it... Also added Route53 for my new server to manage DNS.

Explation from https://stackoverflow.com/questions/40927189/what-is-difference-between-lightsail-and-ec2

EC2, of course, has many more instance families and classes other than the t2, almost all of which are more "powerful" (or better equipped for certain tasks) than these, but also much more expensive. But for meaningful comparisons, the 512 MiB Lightsail instance appears to be completely equivalent in specifications to the similarly-priced t2.nano, the 1GiB is a t2.micro, the 2 GiB is a t2.small, etc.
Lightsail is a lightweight, simplified product offering -- hard disks are fixed size EBS SSD volumes, instances are still billable when stopped, security group rules are much less flexible, and only a very limited subset of EC2 features and options are accessible.
It also has a dramatically simplified console, and even though the machines run in EC2, you can't see them in the EC2 section of the AWS console. The instances run in a special VPC, but this aspect is also provisioned automatically, and invisible in the console. Lightsail supports optionally peering this hidden VPC with your default VPC in the same AWS region, allowing Lightsail instances to access services like EC2 and RDS in the default VPC within the same AWS account.²
Bandwidth is unlimited, but of course free bandwidth is not -- however, Lightsail instances do include a significant monthly bandwidth allowance before any bandwidth-related charges apply.³ Lightsail also has a simplified interface to Route 53 with limited functionality.
But if those sound like drawbacks, they aren't. The point of Lightsail seems to be simplicity. The flexibility of EC2 (and much of AWS) leads inevitably to complexity. The target market for Lightsail appears to be those who "just want a simple VPS" without having to navigate the myriad options available in AWS services like EC2, EBS, VPC, and Route 53. There is virtually no learning curve, here. You don't even technically need to know how to use SSH with a private key -- the Lightsail console even has a built-in SSH client -- but there is no requirement that you use it. You can access these instances normally, with a standard SSH client.

So my understanding of this is, if you ever tried digitalocean or vultr... it's less complicated than EC2 where you need to do everything. I tried this and it's just as simple as creating new server, also there's app on it as well where you can just fire up wordpress server, lamp server and so on.

I decided to try the old fashion way, simple server with no apps in it, turns out great but there's slight need to add in network, where if you need to add HTTPS 443 SSL you need to manually put it. I saw that there's another separate server where you could just fire up a mysql server so I decided to give it a go, I think it's connected to one of their product RDS so I created one server for DB.

After all being created and done, in my main I decided to install just nginx and php, the MYSQL is already being created in other server. So when you connect you application, just add the host to the new DB server... It's a long text hostname.