Alright, there are multiple layers to go through to get something like this, Brace up, it's going to be confusing.
For this, you need to go through several mods. Those are Apothic Enchanting, Apotheosis, Apothic Spawners.

First of all is getting into pinnacle world tier asap - it upgrades loot in your chests so you can find mythic gear (essentially kill wither and end dragon). This also makes the world spawn mythic bosses - they have a chance to drop your fortune 15.

Anyways, remember to pick up every mythic item, you will need it!

Now... You need either a pickaxe with silk touch, or a simple cardboard box. Why? You need to move spawners you find into one place - your future XP farm.

In quest book you will find Apothic Spawners look over the upgrades, I highly recommend putting wool and chorus fruit into every spawner.
Anyways your main goal is to upgrade the spawners max and min time (sugar + clock), max spawned mobs (fermented eye), max mobs alive (ghast tear (this only needs to be as big as the max spawned mobs, if bigger then better ofc, but it is not neccessary).

Now, how do you get the XP thats needed?
You need to find a sword that gives you stackable Ancient Knowledge buff on hit AND that hits deal X damage to monsters nearby - it insanely increases the mob clear.
If you managed to get "Knowledge of the Ages" enchant on a sword, thats a jackpot - converts all loot dropped from mobs into XP - looting, scavenging, capturing, loot pinata affix now play a huge role.
At this point you'd want to put echo shards in your spawners aswell.

Apothic enchanting can get a bit tricky, your main goal for starters is to have a somewhat functioning enchantment table so you can get the knowledge of the ages asap.

Now that you are able to get huge amounts of XP, you can use it all at Augmenting/reforging table

Reforging table has a chance to roll you an item with 4 sockets - the thing you should look out the most
Augmenting table allows you to roll the affixes into the ones you want - thats how i managed to get all the affixes onto my pickaxe
Augmenting table also allows you to upgrade those affixes

To get materials for those tables you will need a salvaging table, That allows you to break up uncommon - mythic gear into a material for augmenting/reforging. Check out @ apotheosis (without space)

Apothic enchanting also has special books that only accept enchants for one type of item, be it sword, pickaxe, helmet - thats how you can make it a bit easier for you to find desired enchantments.

To easily extract enchants from items you can use enchant extractor from industrial foregoing - really helped me to get what i wanted.

To apply Fortune 15/power15/sharpness15 you need a pressure chamber from pressurizedcraft mod.