Visiting England/Wales in late august, early September - looking for places to rent gear and camp

hello, I'm from the US and have never been to the UK. I'm meeting some friends in Bristol on September 1st, but will be driving around southwest england and wales before that for a few days. any recommendations on campsites, places to rent gear, or websites to find places to camp? I asked chatgpt a similar question and it recommended the following for finding locations:

https://www.ukcampsite.co.uk/

https://www.pitchup.com/

https://www.campingandcaravanningclub.co.uk/

and the following for gear rental:

https://www.gooutdoors.co.uk/

https://www.blacks.co.uk/

are these legit recommendations? basically looking for an REI or MEC-like place to rent gear from for a couple days, and something like hipcamp if it exists

any tips you have for camping in the UK are appreciated. thanks.