Hi tkr-bass and welcome
Nice axes.
As regards improving, there's lots of stuff in 'Technique'. You'll find loads of stuff about being in bands in the General Bass Discussion forum (and Off Topic - though some of the stories there might make you decide to avoid the pursuit altogether!)
Either way, it's the same as it ever was. Keep an eye on the ads in music shops; on the 'Bassists wanted and available' here on BC; and on websites like joinmyband, musofinder, gumtree, bandmix, formingbands, partysounds etc. Or even post your own ad. Get a response, shonk off for an audition and see what happens next.
Then you may find you need a gigging rig - and it's the slippery slope to GAS City for you, my lad
Anyhow, Bassists are usually in shorter supply than guitarists, so it's good news all round.
Hope you enjoy the forum