After you logged into Hex Safe, the Dashboard screen shows information across all accounts and assets.
Balance shows the quantity of each asset which changes once the transaction is published on the blockchain.
Available Balance shows confirmed balance of all the transactions that have received network confirmations with a subtracted amount of quantities that are still in progress (if any). The Available Balance might be less than the Balance, if there are transactions in progress.
USD Price shows the US dollar value of one token. The price data is being fetched from a price aggregator Nomics.
USD Value is the value of a particular position which is calculated by multiplying the price of the asset by its quantity.