A method that can be helpful is to copy the STL into an S7-300 project. There it is possible to convert STL / LAD / FBD. See the below picture.

Your sample is a bit more of a challenge.
1) The TON IEC-Timer in the S7-1500 looks a little different.
2) Temporary bits are named in the timer call
                        (S7-300 code would have a raw temporary bit).
3) The STL is not coded in a standard which easily converts.

The last item is especially menacing for someone without experience with STL. It helps a little to think of OR as a [ + ] operator and AND as [ x ] operator for the order of operations. Breaking the code down in smaller parts helps too.

Note the #TempTimer_IN and #TempTimer_Q temporary tags is not visible in the FBD segement. The STL of the first part of the logic was transformed from the following:

A(
O     "Q20.0"
O     "Q20.1"
)
A     "DB90.DBX10.3"
O
A(
AN    "I10.5"
A     "Q20.0"
O
AN    "I10.4"
A     "Q20.1"
)
A     "DB90.DBX10.2"
=     #TempTimer_IN

The FBD solution  looks like:

The LAD version is: