Suppose that I buy a call option at \$10 for a stock $S_0 = \$100$, $K = \$110$, expiry date $T$.
In $T$, $S_T = \$140$, so that I exercise the option to buy and then sell the assets (buy at $\$110$ and sell at $\$140$), thus obtaining a net profit equal to $\$140 - \$110 - \$10 = \$20$.
However, can I just directly take the profit or do I have to buy (at $\$110$) and then sell?
In other words, do I need the $\$110$ to obtain the $\$20$ profit? Or to directly take the profit should I buy a call option on the future of the asset (and thus exercise the call and then sell the future on the asset)?