Hello,

What I usually do is to deploy my applications on a server and then run some stress tests. That way you could figure out how much traffic your applications and server can handle before it gets overloaded.

For more information on how to get started with load testing I would recommend this tutorial here:

https://www.digitalocean.com/community/tutorials/an-introduction-to-load-testing

Also, there is a really good tutorial that goes over how to choose the correct size of your server:

https://docs.digitalocean.com/products/droplets/resources/choose-plan/

Regarding Let’s Encrypt, you could follow the steps here on how to get a free certificate using certbot:

• For Nginx:

https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-20-04

• For Apache:

https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-20-04

Hope that this helps!
Regards,
Bobby