Just maybe the OP is a first timer and really does not understand what you are all telling him, I will give my 2 cents.
When leveling a trailer you need to level side to side first-you do this by getting in your camping spot and check your side to side level-then determine if you are good or need to raise one side-if you need to raise one side you will need something to put under the low side tires-boards, lynx blocks,etc.Now that you have side to side level you can chock tires and unhook and then you can level front to rear with front landing jack-after leveling front to rear now you can put down your rear stabilizer jacks.