You need two XLR cables from the Innopow to the Mackie. Normally these two items are close together so 6' is more than enough but if you have them right next to each other 3' works.
https://smile.amazon.com/Cable-Matters-2-Pack-Microphone-Feet/dp/B00KO8VYMG?th=1
If you're running the karaoke music from the ipad or smart tv to the Mackie you'll need a cable. For Ipads with a 3.5mm headphone output I would use a 3.5mm stereo cable from the Ipad to Inputs 5/6 on the Mackie. If you're running karafun on the smart TV you need to get whatever analog audio output to the Mackie.
Finally, you need a cable(s) from the L and R outputs of the Mackie to the Rockville(s). If you using one Rockville you need a 1/4" dual mono to RCA, something like this
https://smile.amazon.com/Hosa-CPR-202-Stereo-Interconnect-Meters/dp/B000068O17?th=1
For two Rockville speakers I'd use two XLR cables from the L and R outputs on the Mackie to each Rockville.
You don't need an amplifier or audio receiver. The Rockville has a built in amplifier.
This TV doesn't have an analog audio output. You would need to convert the digital audio output to analog with a device like this Prozor
https://smile.amazon.com/PROZOR-Digital-Converter-Optical-Toslink/dp/B00KNNSKV0
You would plug the output of the Prozor into the Yamaha or directly into the Rockville.
To the Yamaha and then to the Rockville you would need two of these
https://smile.amazon.com/Hosa-CPR-202-Stereo-Interconnect-Meters/dp/B000068O17
To the Rockville directly you would need one of these
https://smile.amazon.com/JSAUX-Shielded-Gold-Plated-Smartphones-Speakers/dp/B07D8M5DML
Plugging directly into the Rockville means you would have to use the TV remote to change the volume of the music. Not a huge deal but it's another thing to handle.
I went ahead and ordered the UCA-202 along with these cables -
https://www.amazon.com/gp/product/B01D5H8JW0/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B000068O17/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Hopefully this is better than using VAC.
The 3.5mm cable is a little more common than the RCA but both are pretty much the same.
This would be the RCA cable
https://smile.amazon.com/Hosa-CPR-202-Stereo-Interconnect-Meters/dp/B000068O17
As monchavo said, I wouldn't worry about using one speaker. My advice is to try it out and if want something more you can always buy a 2nd speaker later.
Cables
For mic cables I've used these, they work well and you can get them in various lengths.
From the L R Main Outs on the mixer to the line inputs on the speaker you need something like this. There are others on Amazon if you need it longer.
From the laptop to the mixer I would use this from the headphone jack on the laptop to the channels 11/12 inputs on the mixer
Try to find an HDMI audio extractor with analog outputs. Something like this: https://www.amazon.com/Extractor-Decoder-Amplifier-Converter-Headphone/dp/B08814TNGF . Then use RCA to 1/4" patch cables to connect the analog outputs to your active monitor inputs (https://www.amazon.com/Hosa-CPR-202-Stereo-Interconnect-Meters/dp/B000068O17/)
If the receiver has RCA inputs then you would need a dual mono to RCA cable to connect the mixer to the receiver
https://smile.amazon.com/Hosa-CPR-202-Stereo-Interconnect-Meters/dp/B000068O17?th=1
The low cost speakers I usually recommend is the 10" Rockville
https://smile.amazon.com/Rockville-RPG8BT-V2-Bluetooth-Wireless/dp/B088ZH5CGH