hey there bud First off where off in Europe plays a big part For example here in the UK places like Machine mart Are good places to get tools but probably the best bet is going to be online Amazon and ebay Dont need expensive brands Draper sealey bergen etc will get you started.
I came out of college and straight into a main dealership after 3 years of college and a minimal tool collection i know the problem you are facing really you need to prioritise what you need and that somewhat depends on what they expect you to do.
But to start of with 100% you will need 1/4 3/8 1/2 drive sockets 4mm to 13mm for 1/4 8mm to 19mm for 3/8 and 15mm to 32mm for 1/2
Also as Torx sockets are so common now suggest a 3/8th set from t15 to t55
same with hex sockets a small set from 4 to 12
Spanners you will need at the minimum an 8-19 mm set but preferably a 6mm to 32mm set
Small selection of screw drivers pozi phillips and flat head ( not used so much in EU cars)
Set of long nose combination and side cutters as well as pair of vise grips
Ideally you’d have a set of hammers
Some basic tools for removing damaged bolts easy outs etc ( as a learner you will be braking more than usual and having some basic tools to fix the problem without bothering the other techs goes a long way)
Air tools Really just an impact gun cheap as possible really and just some a 17-19-21mm impact sockets as starting out all you’ll be doing is changing tyres with it
And a budget torque wrench to set the torque on the wheel nuts
Also try and find a cheap tool box best bet is to go onto Gumtree Ebay etc and find a used box If you can a small service trolley would work best as you wont have your own ramp and moving your tools around a lot.
You can get buy in a a garage with that yes you will have to borrow tools but that will get you going.
As for your obd question Stay away from the cheap crap on ebay some of it works some of it doesn’t you can do a lot of damage plugging a car into a computer buy a cheap autel code reader and leave it there for now, you’re company will have a diagnostic machine on site as you wont be doing unguided diagnostic starting out anyway.