Suggestion

Alright just so you know, I was a normal player before too. If I could solo back then you can too.
It's easy to kill a tank, all u have to do is throw a flame grenade while he is burning he moves slower so u can shoot while running, if he gets close u just freeze him and then 1 more flame. U can also go up on some boxes where he can't reach u.

U forgot the most difficult part. Tank is rarely attacking alone and they keep spawning so even if u manage that, it won't last long cuz u won't have any granades for second tank.

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