English isnt my first language so i will try my best to explain, thank you all!

Hi i have a 2010 lexus LS 460 only 94k miles i bought from copart auction. When it towed my shop it was first time i get the see the car in real life and test drive (copart i bought online never seen it before i won the auction) long story short it seems to have a brake problem. All the lights on dash are on(abs, engine check, many more) and it does say brake problem please stop by dealer etc, all. It runs and drives perfectly except for the brake seems hard and doesnt brake immediately when you press on it. I did some research and find out this year has really bad brake actuator and it had been recall and give 10 years fixing warranty whatever (i cant do it because it been over 10 years and the car is salvage title). I looked at lexus dealer website and it say part number is
4405050110 but i think that part is still the bad one according to some post. The actuator that my car has the part number say 4459050090. Am looking at ebay there many for sale remanufactured for sale at 500$ and part number say 4459050070. Im a new mechanic but this is first time ever i will be working on a brake actuator. My question is: 1.do i need to replace brake pump as well or maybe just the actuator will fix my problem. 2. After i replace brake actuator then i will have to bleed, i see many posts it say something about techstream. I have never in my life used a techstream (it looks like a software to me). Do i need to use techstream or obd2 IT2 whatever it calls in order to reprogram. Will the repairs be success without reprogramming or without the techstream. If not i see that on ebay it sell the “cable” and it say techstream license included- is that a software i can download to my laptop and use the cable thing to connect my laptop to the car in order to reprogramming. I attached the picture of the ebay i find here. If its not the right one please post the picture of the techstream i need to buy from ebay please

Any helps are much appreciated