Hi guys I have recently started another project and this one has had nothing but issues, water in crank so crank rebuild and new bearings, engine damage ect . Iv started rebuilding the bike and have noticed there only 2 fixing screw holes on the points plate so no adjustment ? any help would be great how to set up and set timming , thank you 

Timing is set by points gap. So everything being as it should be--a tight 15 thou points gap should give you 1.8mm btdc or very close.
Also there 'should' be a tab as part of the end of one coil. It sits at right angles to the coil screw & should also be a notch in the flywheel window which [everything being as it should] window notch & tab should be 1.8btdc so ideally you're points need to 'just' part company at 'that point'. Then once again--being as it should be--breaking at that 1.8 point should give a max points gap of between 12-15thou.
God i write complicated & confusing lol.
I'll just add--tighten the flywheel good & tight. I know its a 125 but a broken key could ruin your day far from home.
Hope she all goes well & look forward to pics.

There is a manual in the Tech library with instructions. You don't "gap" the points. You set them to open precisely at the correct time.

I agree with MarkT you can set the gap which will get you close if the tab isn’t bent out of shape but you need to use a dial indicator to set your timing the correct way 
PS I don’t gap the points I use a dial indicator only

Ok, fair enough, i've been caught out. All good.
I shouldn't be teaching you my bad habits.
Just trying to get you going without too much fuss by giving it gap within specs & then get serious later.
But i now see you're possibly far from actually running so better do it the proper way.
To make thing easier i guess those have a central spark plug.
Don't forget pics please sometime. We love pics.
Have a happy day!!.