Hello,
Subscript[E, 1] = Series[E^x, {x, 0, 1}] // Normal
Subscript[E, 2] = Series[E^x, {x, 0, 2}] // Normal
Subscript[E, 3] = Series[E^x, {x, 0, 3}] // Normal
Subscript[E, 4] = Series[E^x, {x, 0, 4}] // Normal
Plot[{Subscript[E, 1], Subscript[E, 2], Subscript[E, 3], Subscript[E,
4]}, {x, 0, 5},
PlotLegends -> {Subscript[E, 1], Subscript[E, 2], Subscript[E, 3],
Subscript[E, 4]}, GridLines -> Automatic]

Test[n_] := Series[E^x, {x, 0, n}] // Normal
Plot[{Test[1], Test[2], Test[3], Test[4]}, {x, 0, 5},
PlotLegends -> {Test[1], Test[2], Test[3], Test[4]},
GridLines -> Automatic]

Mathematica 13.2 Notebook file attached.
Thank you.
Attachments: