Cloud Formation vs Terraform

It's usually very individual choice. There are some aspects (not really pros and cons, but just points to which you need to answer):

Are you going to be fully AWS-oriented? If yes, of course you can use both, but if not, you probably anyway (if not now, then in future) will need some additional tools, so in such case Terraform can cover both cases.

Do you already know Terraform? If not, then learning either is probably the same challenge, but if you know Terraform from other projects, you can just start using it. That also apply to your hiring strategy - are you going to look for people who know just AWS (then most likely CloudFormation as well), or in general with some Sys/Dev-Ops experience, then Terraform is a common tool.

There is one another important thing - CloudFormation can't handle existing resources (Terraform usually can, with import, however there are exceptions). That means you can migrate from CloudFormation to Terraform (done it few times, not a big deal in fact), but not the oposite.

I don't want to recommend a tool on itself, but more as an approach: start with CloudFormation and then see if it fits you or not. As mentioned in last point, you can always move to Terraform, but if you start witout CloudFormation, then the doors are closed for you.

Also if you are going to be fully AWS-oriented, CloudFormation can play nicely with more of the services: CodePipeline integrates with it, in case of CI/CD pipeline CloudFormation is a fully managed service (it keeps the states, exposes export values etc.), while in case of Terraform you need to provide own infrastructure for states storage and exposing outputs (you can use for example S3 bucket in AWS for that, but still you need to configure Terraform to use it - CloudFormation is a zero-config in such case).