Ive been playing for two years now and Ive noticed my playing lacks fluidity. what kind of excercises can I do to improve my playing and make it more fluid? Ive also noticed that my hands get kind of tired after playing intricate parts for long on the fretboard and also on my picking hand. I try to do finger picking but my fingers start to hurt after a while.

tl;dr what can I do to improve hand strength and dexterity/ fluidity?
On you fretting hand on the E String fret the 5th fret, then 7th on the A string. Then 6th on the E and 8th on the A. 7th on the E then 5th on the A. 8th on the E then 6th on the A. Then do that along all the strings. It helps me. It may not make much sense reading it how i've typed it but try it out.

EDIT: You need to use all your fingers so go from 1st to 3rd, then 2nd the 4th. Then 3rd to 1st, 4th to 2nd.
For hand strength I'd actually recommend weights. It will improve your grip (even something as low as 5kg) and you should find it easier to fret with.

Other than that there's lots of exercises you can tie in with technique practice and kill 2 birds with one stone
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Long stretches and string skipping exercises are probably your best bet. Try working your fourth finger more. If you build that one up, the other three with also be strengthened considerably.
"Maybe this world is another planet's hell?" - Aldous Huxley
Get the book Bass Fitness by Josquin des Pres. It's a big book of chromatic exercises and nothing else. Go through them slowly, start eighths at 60 bpm, do it for a while then up the tempo a bit until you get it up to at least 180 if not more. Move on to the next one.
If you really want to build up your fretting hand, Bill Dickens swears by a technique he calls the "Buddha Rope." He takes a six-inch length of half-inch thick nylon rope and places it under the strings near where the neck joins the bass body. He then practices fretting the greatly-raised strings up and down the neck. Mr. Dickens claims that for building up fretting hand strength, twenty minutes of this is better than a couple of hours of just playing your bass. I have seen the man play and he is incredible. It is probably worth the fifty cents that the nylon rope costs to find out if it works for you.

I honestly don't know why I haven't tried it myself, but I am going to do so.
"Maybe this world is another planet's hell?" - Aldous Huxley
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I will second JazzRockFeel's suggestion and also recommend spider exercises.

I saw a video on youtube of I guy demonstrating what he called the Spider walk. I find it to be rather helpful.