What do you mean by fixed barbells? Trying to understand what you have available.
What are your goals? Just dropping bodyfat? Improving strength?
I would personally ditch the 3x8 thing and go for a 5x5 routine based around less exercises, more weight and more squats. As a beginner I'd want to be squatting all the time to get my body into omfgmusclemaking mode <--- scientific term right there.
So something like
Monday
Squat
Bench (smith or dumbells in your case I suppose)
Bent over rows (not really sure how well it works with dumbells as I've never tried it, but single arm might be an alternative in this case. Not sure)
Wednesday
Squat
Overhead Press
Deadlift
Friday
Squat
Bench
Bent over rows
All 5x5
--- the next week ----
Switch it around so you do Wednesday's workout on Mon and Fri, and Mon/Fri's workout on the Wednesday. Sort your diet out and throw in some chin ups, dips, core work, and crucially mobility (stretching, getting your shoulders, hips, and anywhere else in your body that's totally and utterly broken from a deskjob), and you'll be on your way to a leaner, stronger, healthier you before you can say "bicep day".
What I have written there is Stronglifts 5x5 followed by adice that I hear repeated on here all the time. Give Stronglifts 5x5 a look triggerthat as you might find it appeals to you. Many people consider it a decent starting out routine, as well as Starting Strength - they're pretty similar incidentally.
Also, make a log thread!