Using the L1 Token Exchange (https://soonaverse.com/tokens/all) is quite a bit different than using your traditional centralized exchange or DEX. It's currently a hybrid centralized/decentralized approach that will become fully decentralized once scripting is available on the IOTA and Shimmer networks. It's centralized because it uses the Soonaverse to create orders. It's decentralized because the Soonaverse only custodies assets while on order is being fully (no need to deposit assets into the system when an order isn't in place).
This means that placing an order is a little bit different as well. Here's a quick tutorial on how to create an order on the L1 Token Exchange: