All tasks have level structure. You can not begin solving task3 if you haven't yet solved task2 from the same type of tasks.
(mini ctf ITMO university just for 3 hours) STEGANO task1:
First of all, it was necessary to run binwalk: binwalk 'task1.jpg' -e
0 0x0 JPEG image data, JFIF standard 1.01 41561 0xA259 Zip archive data, encrypted at least v1.0 to extract, compressed size: 32, uncompressed size: 20, name: first_flag.txt 41765 0xA325 End of Zip archive 41787 0xA33B PNG image, 759 x 141, 8-bit/color RGB, non-interlaced
Binwalk could only pull out the zip archive, which turned out to be password-protected
But we see PNG signature there, try to extract by hands, and find image with password for archive, open archive.
FLAG: 1t_w4s_r34ll9_34zy!