Suggestions for used/new car

Hello, I want to preface this by saying I'm from Europe and I'm not a car guy, I can only do basic repairs/maintance so talk to me like I'm 5

My 30 year old car's engine got destroyed after timing belt broke. So I'm looking for a replacement, my budget for used car (not sure if it's worth spending more in case the car will have issues since it's new? But I'm open to suggestions and could pay more if it's worth it) is around $5000-$6000 for used car (hopefully the prices won't be too different in USA and Europe), but I saw one new model that I liked, in which case I would get a loan, the car is around $19000.

My requirements are that it should be manual, gas, good mileage and could handle around 40 miles daily because of work and of course lower maintenance. I would like a car that's 130hp+, but of course I would settle for less, just got tired of taking forever to overtake or drive uphill with my 70hp car.

I quite like Mazdas, specifically Mazda 6, and then MG ZS, anyone has experience with owning these?

It's not my first language so apologies if it's messy to understand