Supply & Withdraw
In [Markets] click on "Supply" for the asset you want to Supply. Enter the amount you'd like to Supply and submit your transaction.
Once the transaction is confirmed, you begin earning interest.
Each asset has its own market of supply and demand with its own APY (Annual Percentage Yield) which evolves with time.
Suppliers share the interests paid by borrowers corresponding to the borrow rate times the utilisation rate. The higher the utilisation of a reserve the higher the yield for suppliers.
Mostly you can deposit any amount you want, there is no minimum or maximum limit, but for some "risky" assets there is a maximum amount for a market.
In [Markets] click on "Withdraw" for the asset you want to Withdraw. Enter the amount you'd like to Withdraw and submit your transaction.
You would need to make sure there is enough liquidity (not borrowed) in order to withdraw, if this is not the case you would need to wait for more liquidity from suppliers or borrowers repaying.