Welcome aboard alydo12. Lots of people around here have experience with kratom, myself included. It is a wonderful substance; it can help with chronic pain, can be used recreationally as it does produce a mild high, it can also be used to help people relax and/or to get motivated and it's also very effective at helping addicts stay out of opioid withdrawal.
If it's your first time taking kratom then start small and work your way up. A good starter dose is probably around 2 to 3 grams. If you find that is not enough then try a larger dose next time. Some people need more than others, things like natural tolerance, opioid tolerance, stronger or weaker kratom batches, etc can all effect how much you will need.
Kratom has sorta a mild opioid like high mixed with a mild stimulant effect, it's not going to blow you out of the water or anything, but a lot of people do find it very nice in a mellow sort of way. For me it kind feels like a low dose of hydrocodone mixed with a cup of coffee, if that makes sense.
We have lots of discussion about kratom, you can find it by using the search function. A good place to start is the kratom Megathreads if you have lots of free time to kill and don't mind reading tons of posts. Here is a link to the most recent kratom Megathread, there are 5 earlier ones if you search for them:
Kratom Megathread V.6