I run my 1x9 with sora groupset. My set is particular as its 11-34x45 but of 20” wheel so on 700, it is equivalent to 11-34x32T which is plenty enough with the child carrier
but, when comparing the gearing with 45T it s the same as my gravel 11x1 10-42x38T minus the hardest and easiest gears (if i put a 43 or 44, i loose the 2 hardest gears) so as I dont use them much is not an issue.
either way, you may want to create a XL sheet with gearing comparisons to see how usual 11x1 are then look at what 9sp cassettes is available to you and derailleur and set the chainring accordingly.
i personally prefer loosing 2 hard gears rather than having big gaps between gears.