but the question, Who learn more and faster from foreign weapon? China or india?
India, because although beeing far behind China in the industrial field, technologically the gap is not that far in several fields, like radar and engines for example, where China might have get some own developed version into operational service now, but you still are facing techinical and performance issues like India does and remain dependent on foreign stopgaps for the moment. Indian developments in regard of radar are similar (AESA ground and AEW radars, fighter MMRs under development), while the engine development suffers performance issues as well, but are further behind China.
The key point however is, to improve yourself in these fields you have only 2 options
A to spend large ammounts of money and time to fix the problems alone and remain dependent on Russia
B to get the know how from somewhere else, be it from Ukraine as an alternative (which are rare), or the copy from other sources
India on the other side has the 3rd option by going into co-developments with foreign partners, either to fix our problems (Elta for additional modes in LRDEs puls doppler radar, possibly Snecma to fix Kaveris problems), or even our hands on NG technologies. And here you can see the difference of our relation to Russia at best, when you look at what they are offering us:
5th gen fighter co-development (while you still try to get your hands on Su 35 and it's techs)
AESA radars and co-development (Zhuk AE, BARS AESA, Pak FA AESA, while you might get IRBIS PESA now)
NG engine co-development (for FGFA, while you are trying to get 117S engines with TVC and SC capabilites, based on AL31)
MTA co-development
NG helicopter co-development
NG MBT co-development
...
...
...
Add the co-developments we have with Israel and now also France, soon possibly even more European countries and you see that we can learn faster with the access to these partners and higher techs, not to mention that our forces will get stronger as well, instead of waiting for years for low end indigenous stuff.
You still are ahead of us and personally I have no doubt that you will overtake the Russians and even some European countries someday, but it's not deniable that we benefit more currently with our way, the only problem is our national pride that comes in our way often, but that's another story.
Do you know in where is the shipbuilder that building most of USSR carriers? and all know that the training central for carrier of USSR lied in Ukraine, and UKraine have many advanced single technologies, many advanced equipments that left by USSR, all these are we need, and it is easier to get, why not, beside Ukraine
I know and from your point of view, with limited options it's the right way to go for sure, but it also shows that Russia DON'T offer you everything, that they would offer us and that was the point. Otherwise you wouldn't have navalised J15, because Russia rejected the sale of Su 33s.
About the so-called India-Russia joint project, seems you are very happy for these, you just pay money, most of work is did by Russian scientist, you can get all technologies? even you can, you can design and finish the similar project alone later?
I am very happy with such projects, since it gets us highly capable techs and weapons, on a partner level, not only the older export customer level and we get experience and know how of NG techs that we couldn't get otherwise, because we are not at that level yet and countries like the US for example don't share such techs. That's why teaming up for FGFA was clearly the waaaaay better choice for India, than beeing a minor partner, or even just an export customer of the F35.