How to set proper back test range

Question

I do not know how to code and I am trying to learn Pinescript but it really makes no sense to me so i googled how to set a backtest range and used some code someone else wrote but it doesn't seem to be actually testing the area i would like, it tests the entirety of the chart. I'd like to test from 1/1/2018 to present. I'm trying to do this for multiple strategies so I can better tailor them to the current market. here is wat I have for one of them and if you are willing to help with the others I would very much appreciate it!!! feel free to DM me.

//@version=5
strategy("Bollinger Bands BACKTEST", overlay=true)
source = close
length = input.int(20, minval=1)
mult = input.float(2.0, minval=0.001, maxval=50)
basis = ta.sma(source, length)
dev = mult * ta.stdev(source, length)
upper = basis + dev
lower = basis - dev
buyEntry = ta.crossover(source, lower)
sellEntry = ta.crossunder(source, upper)
if (ta.crossover(source, lower))
    strategy.entry("BBandLE", strategy.long, stop=lower, oca_name="BollingerBands", oca_type=strategy.oca.cancel, comment="BBandLE")
else
    strategy.cancel(id="BBandLE")
if (ta.crossunder(source, upper))
    strategy.entry("BBandSE", strategy.short, stop=upper, oca_name="BollingerBands", oca_type=strategy.oca.cancel, comment="BBandSE")
else
    strategy.cancel(id="BBandSE")
//plot(strategy.equity, title="equity", color=color.red, linewidth=2, style=plot.style_areabr)


// === INPUT BACKTEST RANGE ===
fromMonth = input.int(defval = 1,    title = "From Month",  minval = 1, maxval = 12)
fromDay   = input.int(defval = 1,    title = "From Day",    minval = 1, maxval = 31)
fromYear  = input.int(defval = 2018, title = "From Year",   minval = 1970)