the following is assuming you're in the US:

i think in general, and definitely my experience, that getting grad school paid for is considerably easier, structurally. my undergraduate cost me a boatload. my MSc cost me like $400 in lab fees. undergraduate is the "cash cow", but the university runs on exploitable grad student labor through assistantships and tuition waivers for "university employees". this is where you work some almost full time job being a figure-it-out-and-do-all-my-scut for a research lab/team at some R1 school, and then also take 1-2 classes a semester, mostly in that same department that your boss is in, and for your masters research project, you glob on to whatever research project they are running and carve out some little piecemeal research question for your own limited investigation. in theory, you could totally go rogue and dream up whatever question you want, but its easy to paint oneself into a corner.

this is a tricky route because you're effectively signing up to be the serf of some tenure tracked faculty and many younger faculty are careerist psychos who were traumatized by their advisor and are now going to visit that trauma on their own grad students. if you can find an older professor, they can be more chill because they have less to prove. sometimes.

anyway, so you're taking classes, doing that homework, doing scutwork most hours of your day, and also having to learn how all kinds of equipment works and following weirdly complex/ad-hoc procedures. if your relationship with the professor goes bad before you can get your MS, you're kinda fucked unless you can find another prof to take you on and help you across the finish line.

an MS opens more doors into federal and state gov jobs and is about 2-3 years ish for part timers.

Pros:

• you can pause your student loans because you're technically back in school (though if you're going non-profit/state work, i wouldn't. i would look in PSLF.)
• after 2 years as a research tech + MS, you will have enough fodder after that to have an "impressive" resume/CV
• in theory, you are getting paid to go to grad school and develop expertise
• there is a camraderie to being a grad student with other grad students. you're all nerds, you're all broke. they know about cheap housing and bus schedules and cheap food.
• a broadly recognized as respectable way to press pause on entering the job market
• aside from specialized knowledge and experience, in terms of professional development you will get a lot better at written and oral communication in those topics and public speaking more generally. if you suck, you'll become OK. if you're OK, you'll become good. if you're good, you'll become great.

Cons:

• the academy is second only to the military for harassment and bullying. motherfuckers can be toxic AF and the institution will protect them at your expense.
• it fucking sucks to work all day and then have homework and class. my social life and hobbies were fucked.
• the PhD cult will try to recruit you into doing a 5+ year bid instead of a 2+ year bid. a PhD informally closes certain professional doors and has a way of narrowing the horizon to include just the academy. i know people who have made it work and "do well" now, but honestly i don't think the juice is worth the squeeze for mental/emotional development. tenure tracked junior faculty with intact souls are the exception.
• the public university system is very neoliberal anymore and nowhere is this more evident than as a grad student at an R1. the most odious aspect is that the people who are most highly remunerated at these institutions pretend they are public servants and engaging in public intellectualism instead of the most base and vain careerist sophistry. do not dispell their illusions or they will probably try to destroy you.

the way you get into this is looking at job openings at the R1 on campus, in the department that you would want to attend graduate school. you would apply for the job and once you figure out who the professor is that would be your supervisor, tell them you are interested in graduate school and inquire if that's an option. look up everything you can on that professor on their university profile and if you are actually interested in their research, that can really work in your favor in pitching yourself. someone who is curious about what they are curious about and can critically engage with the research is a rare diamond for a research professor. you also want to find a way to have candid conversations with their other grad students and see what they say, but you'd probably have to be stealthy about that.

i don't know if i fully recommend this path, but it exists, i took it out of frustration, and it worked out. if you've worked shit jobs before, you can handle the scut easy.

Yeah. Getting internships in college is important if you want to go into industry, so it's unfortunate the school let you down in this way. Often schools will have career fairs or databases of registered internships through their career office, and those offer higher chances of success than applying from outside channels.