I need Help!!! Plants dying

first time grower and plant was growing well until past 2 weeks my leafs have been turning yellow n now getting brown spots n many others are falling off.. what can i do???

You gave us no information about anything real except that you have plants and their leaves are dying off. Leaves die naturally so unless you give me more information I am just going to attribute it to natural processes.

many leaves are dying by turning yellow curling a little upwards and brown spots are some of them. bottom leaves are turning brown shrinking and falling off.

Post pics plz.. for reference.. whats ur setup?

might be nute or over wtering does your roots have enough space?

u need to post some pics and give the specifics of ur grow

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u need to give the specifics
kinda looks like K or Mg def

It has to do with the nutes for sure whatever it is. I don't think it looks like K or Mg personally but either way there are a lot of variable involved. Luckily all of them basically have the same solution.

Flush heavily with PH adjusted water and end with a proper dose of nutes that are PH adjusted.

I agree flush/adjust/renute.. If that doesnt help check ur roots and look for bugs, They can do big damage but cannot be seen many times.