A Team Lead is a permission level that allows Admin access to a single team. Team Leads are able to manage all the members within their team and are able to add or remove users within their team. They are not able to adjust/move other Team Leads and Company Leads.
How many team Leads should you have?
Ultimately, this depends on the size of your company, the structure of your team, and your business function.
For example, in your typical SaaS Sales Team, each of your specific verticals would be assigned a Sales Manager. This Sales Manager within LEON would be considered a Team Lead.