Dual Monitor For Streaming Purchasing Question

[mLatchi]

Hello all, I have been streaming lately and i thought a second monitor would make my life a bit easier when i want to access streamlabs and twitch chat. I currently have a 144hz monitor that i want to keep either as the primary or secondary monitor, i know nothing about what cables i should use ( i think display ports right), was hoping for general help on monitors and maybe links to decent 2nd monitors, ill link a few that i was looking at and my monitor/specs. Thankyou all sorry if this was a tad convoluted 

(My current) https://www.pccasegear.com/products/29227/benq-xl2430t-24in-led-144hz-gaming-monitor
(looking at) https://www.kogan.com/au/buy/acer-245-169-1920x1080-240hz-full-hd-led-monitor-kg251q-acer/
(and) https://www.umart.com.au/Acer-KG271B-FREE-SYNC-27-TN-LED-16-9-1920x1080@240Hz-1ms-DP-HDMI-1-4-HDMI-2-0-Tilt-VESA-SPK_41282G.html

SPECS:
cpu: i7-8700k
gpu: OC 1080ti (nvidia)
ram: 32gb ddr4
ssd: 970 EVO

WIll answer any comments not really sure what information is needed to make a decision!