Here are some facts about Nuclear power. Every country has stolen Nuclear designs from Germany. Nazi scientists during 1930 and 40s made tremendous breakthrough in splitting atoms. There are many documentaries on YouTube about it. USA got hold of Nuclear Tech when Jewish german scientist deflected to US. Some Pakistanis were also in German Universities and if I am not wrong few of them were also involved in Manhattan project. Similarly, USSR, UK and other countries got Nuclear technology after taking over Germany.
Now your assumption that Pakistan is not making progress and somehow Indian is, Is not true. World know Pakistan Nuclear program is way advance than India. Pakistan has the fastest growing nuclear arsenal. Russia helped India. Pakistan's western technology is better than Indian Russian tech. Pakistan is the first associate member of European Organization for Nuclear Research (CERN) and only non-European country to achieve this status. Pakistan scientist won Nobel prize in Physics. Pakistani scientist are working on The Large Hadron Collider (LHC) , the world's largest and most powerful particle accelerator.
Pakistan contributed to building the CMS and ATLAS experiments for this. Pakistan contributes today to the ALICE and CMS experiments. Pakistan is also involved in accelerator developments, making it an important partner for CERN
Europeans and US got it easy, and than they helped each other without sanctions. It cost money, lots of money to build and run a nuclear program. Considering international sanction, and ban on transfer of Nuclear technology, running a fastest growing nuclear program is no small feat. Just to get coating application ( special epoxy Paint) for Nuclear plants will land you in international prison.