From the browser you can use a key signer like @Alby or @LNbits shop signer like this:

LNbits Shop

Nostr Signing Device (NSD) - LNbits Shop

Build your own nostr signing device using off the shelf hardware. When used as a hardware wallet can be used with the LNbits onchain extension. ...

But sometimes, unfortunately, you do have to expose your nsec. NOSTR is very much an evolving protocol. Over time you’ll work out the best range of services for you and which ones you wish to pay for. I hope you can stick with the journey. I think it’s worth it. Plus I’ve had a look through your posts and like a lot of your art. I think you’ll find an audience here and you might even find it pays well.