Slave cylinder seal leak

If there are no leaks, it sounds like master cylinder is faulty (fluid is by passing seals) because it's a new cylinder It doesn't mean it's not faulty

Hello. It seems your vehicle's transmission has to be rebuilt/replaced. Any automatic transmission that won't 'shift' from 1st gear into 2nd or 3rd gear has a 'worn' slave cylinder that 'slides' gears one way or another. 1st gear works yet 2nd and 3rd don't. Good luck and keep me informed; if you want to.

master cylinder for sure possibly due to fluid contamination. DOT3 and Dot4 fluids cant be mixed . causes softening of seals in cylinders much like if contaminated with mineral oils

You are in the wrong section of FixYa, but I can help you.
The reason why you are having trouble changing gears is your clutch is not disengaging properly from the engine when you press the clutch peddle.
If the clutch is a cable type control, then the clutch cable and clutch lever may need adjusting to disengage the gearbox from the engine so you can change gears without crunching the gears.
If the clutch is hydraulic type, you could have air in the system or you have leaky hydraulic seals, both of which will prevent the clutch from disengaging from the engine properly. Check the clutch master cylinder and the clutch slave cylinder for leaks. If there are leaks you need to replace the seals and if the master and slave cylinders are badly scored then they need to be replaced as well.
If there are no hydraulic leaks then bleed the hydraulic line to remove the air in the hydraulic system, you may also need to adjust the push rod from the slave cylinder to adjust the clutch lever arm so when the clutch peddle is depressed the clutch fully disengages the engine.

more than likely the slave cylnder in the tranny or on the side of the tranny have you been seeing fluid on the ground.

I just recently experienced the same thing.  I drained all the fluid out of the clutch master throught the slave cylinder and refilled it with new fluid.  Bled the system really good and now it works just like new.  If this does not help you may need to remove the slave cylinder and replace the seals if it is leaking.
Good luck1

CHECK FOR ANY LEAKS STARTING AT MASTER CYLINDER THEN CHECK SLAVE CYLINDER AT G/BOX IF OK THEN BLEED CLUTCH MASTER CYLINDER OR SLAVE CYLINDER MIGHT HAVE WORN SEALS IN THEM THOUGH SO PARTS MIGHT NEED REPLACED.