I am okay with spreadsheets I am just not sure what I am doing with them. I can add and subtract, but I am not sure how to use the detailed calculations that a lot of the users here mention doing. I have read through MMM's entire site and many others so I don't believe I am not educated about FIRE and am looking for shortcuts... but I am just unsure of how to apply what I've learnt to our particular situation. Some say portfolio assets should cover expenses, some say backdoor roths, some say 401K withdrawals with 10% penalty. I think the fact that I have read to much is actually leading to so much confusion! I guess at this point I am just not sure what investing buckets I should be focusing on because I don't have an actual strategy other than 25x expenses.
The real problem is that you are conflating multiple different concepts together. "Portfolio assets should cover expenses" is the end goal: you want to save enough that a 4% withdrawal rate will cover your expenses (i.e., 25x your estimated retirement expenses). Backdoor Roths are a tool you can use to get money in a tax-sheltered account if you don't qualify for a traditional IRA. And a 401(k) withdrawal with the 10% penalty is a tool you can use to take your money out of your 401(k) before you turn 59 1/2. See how different those things are? Same with the general reference to "spreadsheets": Spreadsheets themselves are just a tool that can be used for many different things, from budgeting to projecting future income/returns to tracking expenses, etc.; you can know how to work Excel and still not track how some of the detailed analyses people use here work (ask me how I know!).
Don't let the perfect be the enemy of the good. Your number one goal right now is to build up your assets as fast as you can. That means two things: (1) saving/investing as much money as you can; and (2) keeping the costs down on those investments. (1) is self-evident. (2) is just limiting the drains on (1). And there are two primary sources of those drains. First is the tax man: when you invest in a regular account, you are putting in dollars after taxes, which means you have fewer dollars to invest in the first place, plus Uncle Sam takes a cut of your earnings every year. So the solution to that is to put as much into tax-sheltered accounts as possible, starting with prioritizing the accounts that get you the most tax breaks. So for the vast majority of people, that means (a) HSAs (don't pay taxes on money you put in initially AND money grows tax-free AND it is tax-free to take it out if you use it on medical expenses = 3 tax breaks!); then (b) 401(k)/IRA (don't pay taxes on money you put in initially AND money grows tax-free = 2 tax breaks); then (c) Roth 401(k)/Roth IRA (money grows tax-free AND you don't pay money when you take it out = also 2 tax breaks, but usually not as advantagious as (b) because you are usually taking money out in a lower tax bracket than when you put it in).
The other drain is investment costs, i.e., the fees you pay on your investments. This is why people here tend to prefer Vanguard/Fidelity, and prefer index funds or ETFs: you don't have to pay an adviser or broker to invest, they have wicked low management fees, and they don't rack up a lot of extra costs by trading frequently to try to beat the market (which no one really does long-term). This is where people have to debate whether to prioritize 401(k) or IRA: some 401(k)s don't offer a great mix of funds, so if you are stuck with high-fee accounts, you want to prioritize your IRA. OTOH, some 401(k)s offer matching funds, which are basically free money, so unless your 401(k) is truly horrendous, you want to at least put money in up to the match before diverting savings to your IRA.
And that's it. Dump a metric shit-ton of money into your HSA, 401(k)s, and IRAs, focusing on the lowest-cost broad-market options they have, and then save extra in a taxable account if you need to to hit your target. No spreadsheets even required.*
But wait, you say -- what about all of the other stuff, like rolling over my IRA into a Roth, or the 401(k) 10% penalty thing, etc. etc. etc.? Don't worry about it!! Those are things that matter when you need to access the money -- so if you are more than 5 years away from needing the money, you have
plenty of time to read and learn more before you get there! So again, don't let the perfect be the enemy of the good: focus on the wealth-building for now, and trust that you are smart enough to learn all about tax-favored withdrawal strategies by the time you get there.
*FWIW, I can barely even use Excel and have no interest in learning. If I want to project what my investments will be in however many years, I just use one of the gazillion internet sites that will do the math for me. No, it is not precise, but neither is life, so it serves my needs just fine.