To replace U Joints you only need a hammer such as a ball peen hammer and a pair of needle nose pliers.
The ball peen hammer usually works great for pounder out the U Joint Caps and also for pounding the new ones back in.
Although you can use a regular hammer with something else to help drive the caps out and back in.
You should not use a shop press when removing U Joints as it can bend the driveshaft yoke and cause vibration when the driveshaft is reinstalled.
I just use a ball peen hammer and hammer the U Joints out.
The needle nose pliers are also needed to remove the keeper pins that go above the caps to hold them in.
On some U Joints you may need to use a small torch to melt the plastic out but most U Joints just need a hammer and a bench as well as needle nose pliers.
You have to remove the driveshaft to replace the U Joints so you need sockets to remove the bolts holding the driveshaft on as well.
There are tiny needle bearings as well in the U Joint Caps so make sure you are working on something such as a concrete floor or wood floor or have a bucket beneath the U Joints when installing the new ones because you could lose those tiny needle bearings in the ground.
I have done that and had to get more U Joints.