I want to know my actual IQ but I have no idea where to start. There are tons of free tests online that give you a score in 10 minutes but I have heard those are basically meaningless. I also know that proper clinical assessments exist but those seem expensive and hard to access. What are my actual options and how do I evaluate whether a test result is giving me a real number or just telling me what I want to hear?
The free 10 minute tests are almost universally garbage and honestly kind of insulting 
Real IQ assessment needs a large normed population sample, enough cognitive domains to estimate g reliably, and published reliability data. The gold standard is a clinical assessment like the WAIS but that costs hundreds of dollars. A legitimate middle ground is something like RIOT IQ which covers 15 subtests across 6 CHC domains with actual psychometric foundations behind it 
That is a completely different category from the viral quiz sites that just tell you what you want to hear.
The tell for a fake test is usually that it takes under 15 minutes and gives you a suspiciously high score 
Real cognitive assessment takes time because it has to sample enough of your ability across enough domains to estimate g reliably. If you finished in 10 minutes and scored 140 you did not just discover you are a genius, you got flattered by an algorithm 