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We can get an infinite amount of Taka from the machine.
Let $n_k$ denote the amount of money we have after $k$ exchanges with the machine. If we give the machine $x_k$ Taka s.t. $x_k>7$ in the $k$'th exchange, then the machine will return $2(x_k-7)=2x_k-14$ Taka. So, \[n_k=n_{k-1}-x_k+2x_k-14=n_{k-1}+x_k-14\]
So, if $x_k\geq 15$, then $n_k\geq n_{k-1}+1$.
We have $2023$ Taka in the beginning, so we can clearly give the machine 15 Taka in every move. So the total amount of money always increases by at least $1$.
$\therefore$ We can get an infinite amount of money.