5 GHz blistering fast - 2.4 GHz extremely slow

So my question is twofold:
1) Can I force my devices to connect via 5 ghz? I know I can turn down the signal strength on 2.4 ghz but this is not a preferred workaround as I need a strong 2.4 ghz signal when I move around my garden and have some distance to my access point.----No, orbi is designed for bandsteering. I don't have the orbi AX series but with my AC orbi's after a few days, the orbi devices learn which device needs which band. the first few days it tends to automatically put devices on the 2.4ghz and switch them to 5ghz. After the adjustment period, some devices will automatically go to 5ghz. But it takes a little time to settle. Again, this was with my AC system. Not the AX

2) What possible reasons could be for my extremely slow 2.4 ghz connection?-----Because its how 2.4ghz is. 2.4ghz is much slower but broadcasts further and through more materials. its the whole reason for 5ghz....more bandwidth. Plus its more sensitive to interference because it has less channels available. My AC system (and other's I've used) is. If you live in a rural environment without any interference, you potentially can see faster speeds. But in an environment with multiple wireless signals present, its much slower than 5ghz. 

Hoping for some good inputs. Thanks in advance😊

/Ramboost

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