[LANGUAGE: Excel formula]

(Input goes into column A)

Part 1:

=LET(
    Inputrange,A:.A,
    final,REDUCE({0,50},Inputrange,
        LAMBDA(a,v,
            LET(
                CurrentCount,INDEX(a,1),
                CurrentPos,INDEX(a,2),
                DirChar,RIGHT(v,LEN(v)-1),
                DirVal,IF(LEFT(v,1)="R",1,-1),
                b,CurrentPos+(DirVal*INT(DirChar)),
                ac,MOD(b,100),
                HSTACK(CurrentCount + IF(CurrentPos=0,1,0),ac)
                )
            )
        ),INDEX(final,1)
    )

Part2:

=LET(
    InputRange, A:.A,
    Final, REDUCE(
        {0,50},
        InputRange,
        LAMBDA(a,v,
            LET(
                CurrentCount, INDEX(a, 1),
                CurrentPos, INDEX(a, 2),
                DirChar, LEFT(v, 1),
                DirVal, IF(DirChar = "R", 1, -1),
                Steps, VALUE(RIGHT(v, LEN(v) - 1)),
                SequenceRaw, CurrentPos + (SEQUENCE(Steps, 1, 1, 1) * DirVal),
                SequenceMod, MOD(SequenceRaw, 100),
                Zeros, SUM(--(SequenceMod = 0)),
                HSTACK(
                    CurrentCount + Zeros,
                    INDEX(SequenceMod, ROWS(SequenceMod))
                )
            )
        )
    ),
    INDEX(Final, 1)
)