You can borrow USDT, USDC, DAI, and NXUSD, depending on which region you are in. For full availability please check your Wirex App. 

The following currencies are available as collateral (depending on the region you are registered in):  
ETH, WXT, BTC, YFI, MKR, AAVE, UNI, COMP, LINK, 1INCH, SOL, AVAX, MATIC, DOT, ALGO, ADA, TRX, WXT, XRP, XLM, LTC, DOGE, SHIBA, AXS, APE. 

The borrowed amount depends on the collateral that you add and the allowed LTV ratio of it. 
 
For more information about the borrowed amount and the LTV, please check this page.