Jill, if you're looking for a good mic, I suggest contacting Don Mason - he has more in his music room that most music stores have in stock. I would suggest the Sennheiser E series, which provide absolutely superb vocal quality and great feedback rejection.
As for software, if you're looking for multitrack you might want to start out with Audacity, which is a great program with a huge number of features, very user friendly, doesn't require an interface to your PC and is free at
https://audacity.en.softonic.com/download . The program was created by Sound Forge, which is one of the programs I purchased many years ago, has many of the same features, and the end results are outstanding. Many of the PSR Tutorial members use Audacity and report excellent results.
When I was still working as an entertainer, I used a Crown CM311A headset mic, mainly because of the freedom a headset mic provides an OMB entertainer. The quality of this mic is fantastic, but it comes with a hefty price tag, about $359 at most locations online. In the local music stores here, they add another $100 to that price.
I wish I could be of more assistance, but today, I feel fortunate to be able to sit in the office and type this post.
Good luck, young lady,
Gary