I would highly recommend connecting with someone who has experience here to shorten your learning curve if this is not what you do.

For our agency, we spent a lot of time & money outlining and creating the infrastructure which now is mainly on autopilot for our outbound strategy. For example, we now have a small team running it while sending on average 5-10k emails per month consistently. I can help outline how to do the same thing as well.

Team-wise I would lean in the direction of learning the framework, building a small team and launching some base campaigns internally. I have looked and hired a lot of 3rd party companies that claim to handle all your outbound campaigns but most are 5/10 quality wise and charge a hefty premium.

Once you know the structure it mainly comes down to team building, having a quality product/service, and creating value through very personal outreach campaigns.

Resources wise- there are some great books out there on this. I would highly recommend "The Ultimate Sales Machine" by Chet Holmes and "Predictable Revenue" by Aaron Ross. These both will give you a lot of higher level ideas and ways to structure your outbound campaigns. A lot comes down to your internal resources and budget as well.

Hope this helps!