Unlike County cricket, the internationals play to packed stadiums and have great atmosphere. Whether it's Test matches or ODI's they are long days for the photographer with 7-8 hours of full on action and image capture. This length of time means you have to think differently about the gear that you bring.
Firstly, bring a comfortable seat ! Those small fold-away stools that are so convenient for 90 minute football will numb your backside over a much longer time period - they also tend to be low down and thus cramp your legs. So, bring a comfortable leisure seat that will ease the strain. The second point is that cricket is very suited to long focal length (and therefore heavy) prime lenses so bring a tripod and a gimbal head to give your set up a sturdy feel - a monopod will be hard work.
On the subject of lenses I use a Canon 600mm f4 for cricket, perhaps a 500mm will be good enough with an extender but much less than that and you will be de-gradinmg image quality with significant cropping.
My experience as an ECB accredited photographer is limited to Trent Bridge in Nottingham and Old Trafford in Manchester for the England v Australia ODI series in June 2018. It was a real luxury at Trent Bridge having ethernet cable and power for my laptop delivered to my seating position. This meant I had no problem wiring out images or seeing my laptop battery run down - which it would do after 4-5 hours of use. Old Trafford was wifi only but it worked superbly fast - very unusual for wifi !!
There is no 'best position' to sit at cricket. Just try to get as good a head on view of the batsmen as you can but be prepared for fielders to constantly get in your way - so be prepared to move. Personally, I like sitting near to where the batsmen will walk back to the pavilion when they are out - if they have had a mediocre innings you can capture their disappointed emotions, if they have scored really well the emotions are more joyous with bats raised in appreciation. But in any case be prepared to wander around to get high up shots from the top of grandstands and any good humorous images of fans Always be on the look out for the unexpected.
The most usual question I get is ..."do you take pictures of every ball being bowled ?" No, I don't, when you get used to it you start to envision the shots that you want to get and what that means in terms of the batsman's upper body and arm movements. If he/she starts to angle their frame and arms in the direction of the shot that you want then go for it and press the shutter on continuous shooting mode. If they don't and they point away from you then I don't bother - so it's all split second stuff. Bowlers are easier to shoot as they run in in quite a consistent way and probably the hardest shot to get is the fielder making a catch as you really have to have a good tracking eye for the ball and which direction it is going.
As cricket is a summer sport played usually in bright sunny days it's great for getting some good quality into your images with high (1\3200th sec) shutter speeds and low (200-400) ISO's. There is such a difference between this and a football match in the middle of winter under poor floodlights.
Because there is lots of action over lots of hours you are bound to take lots of images and the delete rate will be high as the amount of near-duplicates is high and the often hoped for action does not materialise in the way you thought. So on a typical day I would probably come away with 3000 images and of these I will only keep my top 300 - thats the beauty of digital !