You can't schedule a recurrence in flow like that currently. You can go to ideas.powerautomate.com and submit an idea and if it gets enough votes it will be considered.
For what you want to do, it will have to be triggered every Tuesday, but you setup the flow to check if it's the third Tuesday or not. If it is not a condition action would contain a terminate action to stop the flow from doing anything further.
What you need to do to make this work is create a compose action and create an expression to with this formula:
dayOfWeek(utcNow())
Then follow the link I posted previously to calculate the week of the month. Once you have those two pieces of information, you create a condition action. The condition you are testing for is the output of the dayofweek, and the week number. So dayofweek eq 2 and weekofmonth eq 3 (day of week could be a 1,2,3 depending on how your system is setup if Monday starts the week or Sunday does, most the time it should be Sunday, but I can't remember if Sunday is 0 or 1)
