You can add tokens to the available liquidity pools by selecting the corresponding pair, i.e. EGLD/UTK in the LIQUIDITY section on the xPortal DEX.
The deposit of the two tokens must always be an even 50:50 ratio (USD value).
In return, you will receive EGLDUTK LP tokens that can be transferred between wallet addresses or further staked in the farm. More info on how to enjoy all of these advantages here.
You can remove liquidity by giving back your LP tokens. They will be burned and you will receive the amount of EGLD and UTK based on the current ratio between EGLD/UTK (this might be different than what is was initially), plus your share of the swap fees on the EGLD/UTK pair for the period when you have provided the liquidity.
If you want to better understand the risks of doing something like this, please refer to the Impermanent Loss explanation provided here.