got my new imac 24 it only has 2 thunderbolt ports need more usb ports and is there adapters for thunderbolt to usb

Welcome to the Apple Support Communities.

This is a simple adapter for what you need: USB-C to USB Adapter - Apple.

You could also look at a dock for more ports, such as the CalDigit TS3 Plus Dock - Apple or the CalDigit Thunderbolt 3 Mini Dock - Apple.

Jack

apart from what the rest says then you realise that the thunderbolt ports are at the same time usb-4 ports using the usb-c connector which both thunderbolt and usb-3 and usb-4 uses and one can get converters from usb-c to usb-a (the port you likely view as an usb port)

There are many. Easiest: search Amazon.

USB C plugs into the Thunderbolt ports. I also have a new iMac, although with two Thunderbolt and two USB ports. My two USB drives are plugged into the Thunderbolt ports at the mement, and run fine.

If you want more TB ports you will need a dock like the Kensington SD5700T Thunderbolt 4 Docking Station. It adds an additional 3 TB ports plus other connections.

I got the owc Thunderbolt 3 dock, and it works just fine:

https://eshop.macsales.com/shop/docks/owc-thunderbolt-3-dock