(How's the driving instruction going?😁)
Ref working with plasticard have a look at the links here, something there should spark you off💥💡😉
Are you working to a plan? If not - MAKE ONE! At least accurate sketches of major parts.
Cover the plan with tracing or baking paper then you can glue bits together on it accurately without getting into a 'stick up' with the plan. Use a thin plastic glue that you can brush on and it should run into long joints by capillary action.
To reinforce the inside corners I use square or L profiles. If the corner is not 90° I cut appropriate brackets from thicker plasticard ca 1/8" (3mm).
Used the same techniques (except for thin plastic glue😁) with 0.5mm ply for the superstructure of scratch built 1/72 destroyer. I glued up with thin waterproof PVA.
Hope this helps.
Cheers, Doug 😎
PS Your destroyer HMS Temerity is very similar to my scratch build, HMS Hotspur. See pics.
Made to plans I scaled up from an Airfix 1/600 kit when I was 15. Since been rebuilt, twice😁