Bhasha Pravesha, Gita Sopanam, Pravesha all these three in the same level.
Gita Sopanam has four levels Gita Sopanam (Level 1), Gita Sopanam (Level 2), Gita Pravesha (Level 1), Gita Pravesha (Level 2)
Bhasha Pravesha has two levels (Level 1, 2)
Pravesha has 4 levels (Pravesha, Parichaya, Shiksha, Kovida). Exams are conducted by samskrita bharati across the globe.
My suggestion is, you can take Gita Sopanam (Level1). If you can follow, you can do Gita Sopanam Level 2 too.
Gita Sopanam and Bhasha Pravesha are the same. Only exercises are different. In GS you will find exercises related to Gita/Mahabharata. For Bhasha Pravesha, you will find exercises based on regular usage of sanskrit.
I would recommend you to do Gita Sopana series (links below) along with exams like Pravesha, Parichaya, Shiksha, Kovida
Hope this helps.