Oumers Bike Cassette Removal Tool, Cassette Freewheel Removal Tool with Chain Whip and Auxiliary Wrench Bicycle Cassette Lock Ring Extractor, Freewheel Remover Wrench Sprocket Remover

First make sure if it is a cassette or a freewheel. https://youtu.be/iTJ3taJHOn8?si=ydHhtw5ySFQV25kq You don’t have to buy the Mercedes Benz quality Park tools. Oumers are Ford of bike tools and work fine. https://a.co/d/09Au526C I’ve had good luck with these Bucklos cassettes. https://a.co/d/03FRzl5p Keep the range at 11-40T and it is under $30. If you do go for a wider range cassette you will need a longer chain. OR Stick with the same range and just use the existing chain. YouTube university is your friend.