[Volume-Volume].How many liters of HF gas will be produced when 30.0 liters of hydrogen reacts ?

Equation:h2+f2--->2HF

i need help

You need help in more than one way. FIRST, learn to write the equations correctly. That is

H2 + F2 ==> 2HF
You can do this the long way or the short way. The long way is to convert 30 L H2 to moles H2 (30/22.4), convert moles H2 to moles HF, then convert moles back to volume, moles x 22.4 = volume.
Short way is to recognize that since we divide by 22.4 on one step and multiply by 22.4 in the other step, we can short circuit that and omit the 22.4 part. Said another way, the moles of a gas are proportional to volumes. So
30 L H2 will produce 2 x 30 = 60 L HF.