can someone plz tell me how to make a varrock teleport tablet?

You need to find or create a house with a study, and a lectern. Then use the lectern and you will get the option to make a tele tablet.

 

You need soft clay as well as the tele runes for the spell.

what construction lvl do i need for that?

For just the basic lecturn, you need lvl 40 construction. 67 is for mahogany, and 57 for teak. Teak works perfectly fine. The only thing you can't get is this house teleport, and the watchtower teleport. But you can always move your house to somewhere near a teleport if you need.