I linked this page on my fanbox cause I use fanbox as a way of payment for commissions.
Each tier on fanbox gets points every month:
These points are permanent, once you get them even if you stop pledging your points will still be there if you ever come back.
Each consecutive month some tiers also get bonus points, tho unlike normal points, if you remove your pledge you lose all bonus points you have accumulated.
if you're not planning to get a commission I would recommend to only pledge on "fan"
for commissions I open a number of slots at a time, I will post about it on pixiv, baraag and also discord if you're there.
Just keep in mind that I may not be available at the moment you get enough points for your commission.