I haven't fostered, but my personal and professional lives bring me into contact with many people who have (as well as social workers, therapists, etc.). I do have two adopted daughters, one of whom came to us through the foster care system. We plan to foster and/or adopt older children and teens in the future, when our lives are more settled and the girls are older.
I agree with everyone who said that there is a HUGE need, and that it's a tough road. If it's a good fit for you it can be incredibly rewarding. I know people who've fostered over 100 kids/teens and are still involved in "the system" with a positive, hopeful attitude. They change lives every day, and sometimes literally save them. Those people are my role models and my heroes.
Almost everyone I know who has fostered or adopted from the foster system works and is either single, or also partnered with a working spouse. It's do-able for sure, although logistics can get tricky with appointments and visits. You need a very strong support system.
I think it's important to go into it with the awareness that all foster kids will have extra needs of some sort, be they emotional, behavioural, mental illness-related, brain injury-related (FASD, TBI), learning challenges, etc.
The best thing to do right now would be to see if you can get some volunteer work with similar populations, and do as much reading as you can. I can offer suggestions.
I'm so happy you're considering this. It's impossible to underemphasize how enormous the need for committed, loving, safe foster homes is.
I'd be happy to talk more specifically via private message about my personal experience and my professional knowledge, if you want.