Newbie here, so go slow and gentle please.
I've currently got a Whyte 603 Hardtail MTB that I'd like to convert, 73mm bottom bracket running on 27.5" wheels

I'm a big lad, approx 120kg and currently tend to ride a mixture of tow paths and other flatish trails. I'd like some help to get up some of the steeper climbs around here(Stroud, UK) and enjoy some longer rides.
Where do I start, it's all so confusing!
Front hub, rear hub, or mid drive? Budget upto £700ish
Integrated lights would be good, walk assist essential.
Torque and range more important than speed. Remember this is to get me up hills and on longer rides, not a speeding ticket!
I'm relatively hands on with bike maintenance and will try most jobs, although pulling the crank and changing the bottom bracket would be a new challenge for me.
Fire away with suggestions please!
I've currently got a Whyte 603 Hardtail MTB that I'd like to convert, 73mm bottom bracket running on 27.5" wheels

I'm a big lad, approx 120kg and currently tend to ride a mixture of tow paths and other flatish trails. I'd like some help to get up some of the steeper climbs around here(Stroud, UK) and enjoy some longer rides.
Where do I start, it's all so confusing!
Front hub, rear hub, or mid drive? Budget upto £700ish
Integrated lights would be good, walk assist essential.
Torque and range more important than speed. Remember this is to get me up hills and on longer rides, not a speeding ticket!

I'm relatively hands on with bike maintenance and will try most jobs, although pulling the crank and changing the bottom bracket would be a new challenge for me.
Fire away with suggestions please!